Consumer medicine information

Postrelle-1

Levonorgestrel

BRAND INFORMATION

Brand name

Postrelle-1

Active ingredient

Levonorgestrel

Schedule

S3

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using Postrelle-1.

SUMMARY CMI

POSTRELLE®-1

Consumer Medicine Information (CMI) summary

The full CMI on the next page has more details. If you are worried about using this medicine, speak to your doctor or pharmacist.

1. Why am I using POSTRELLE-1?

POSTRELLE-1 contains the active ingredient levonorgestrel. POSTRELLE-1 is an emergency contraceptive used to prevent pregnancy when taken within 72 hours of unprotected intercourse.

For more information, see Section 1. Why am I using POSTRELLE-1? in the full CMI.

2. What should I know before I use POSTRELLE-1?

Do not use if you have ever had an allergic reaction to POSTRELLE-1 or any of the ingredients listed at the end of the CMI.

Talk to your doctor or pharmacist if you have any other medical conditions, take any other medicines, or are pregnant or plan to become pregnant or are breastfeeding.

For more information, see Section 2. What should I know before I use POSTRELLE-1? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with POSTRELLE-1 and affect how it works.

A list of these medicines is in Section 3. What if I am taking other medicines? in the full CMI.

4. How do I use POSTRELLE-1?

  • Take 1 tablet as a single dose as soon as possible after unprotected intercourse and no later than 72 hours (3 days) after intercourse.
  • Swallow the tablet whole with a full glass of water. Do not chew.

More instructions can be found in Section 4. How do I use POSTRELLE-1? in the full CMI.

5. What should I know while using POSTRELLE-1?

Things you should do
  • Remind any doctor, dentist or pharmacist you visit that you are using POSTRELLE-1.
Things you should not do
  • Do not take this medicine if you had unprotected intercourse more than 72 hours earlier in the same menstrual cycle.
  • Do not take this medicine if you are pregnant.
Driving or using machines
  • Be careful driving or operating machinery until you know how POSTRELLE-1 affects you.
  • POSTRELLE-1 may cause dizziness or light-headedness in some people.
Drinking alcohol
  • Tell your doctor or pharmacist if you drink alcohol.
Looking after your medicine
  • Store the medicine in a cool, dry place where the temperature is below 25°C.

For more information, see Section 5. What should I know while using POSTRELLE-1? in the full CMI.

6. Are there any side effects?

The most common side effects are tiredness, nausea and vomiting. Other side effects include stomach pain, diarrhoea, dizziness, headache, tender breasts, increased vaginal bleeding and skin reactions.

For more information, including what to do if you have any side effects, see Section 6. Are there any side effects? in the full CMI.



FULL CMI

POSTRELLE®-1

Active ingredient(s): levonorgestrel

Consumer Medicine Information (CMI)

This leaflet provides important information about using POSTRELLE-1. You should also speak to your doctor or pharmacist if you would like further information or if you have any concerns or questions about using POSTRELLE-1.

Where to find information in this leaflet:

1. Why am I using POSTRELLE-1?
2. What should I know before I use POSTRELLE-1?
3. What if I am taking other medicines?
4. How do I use POSTRELLE-1?
5. What should I know while using POSTRELLE-1?
6. Are there any side effects?
7. Product details

1. Why am I using POSTRELLE-1?

POSTRELLE-1 contains the active ingredient levonorgestrel.

POSTRELLE-1 is an emergency contraceptive only. POSTRELLE-1 is not intended as a regular method of contraception.

It is used to prevent pregnancy when taken within 72 hours of unprotected intercourse (sex).

It is estimated that POSTRELLE-1 will prevent 85% of expected pregnancies when you take it within 72 hours of having unprotected sex. It will not prevent a pregnancy every time and is more effective if you take it as soon as possible after unprotected sex.

POSTRELLE-1 is most effective if taken within 72 hours of unprotected sex. The sooner that you take POSTRELLE-1 after unprotected intercourse, the more likely it is that the medicine will work.

POSTRELLE-1 is thought to work by:

  • stopping your ovaries from releasing an egg
  • preventing sperm from fertilising any eggs you may have already released

Therefore, POSTRELLE-1 stops a pregnancy before it is established. It does not work if you are already pregnant. If another unprotected intercourse takes place after the use of POSTRELLE-1 (also if this is during the same menstrual cycle), the tablet will not be effective and there is again the risk of pregnancy.

POSTRELLE-1 will not prevent you from catching sexually transmitted diseases.

2. What should I know before I use POSTRELLE-1?

Warnings

Do not use POSTRELLE-1 if:

  • you are allergic to levonorgestrel, or any of the ingredients listed at the end of this leaflet.
    Always check the ingredients to make sure you can use this medicine.
    Some of the symptoms of an allergic reaction may include:
    - shortness of breath
    - wheezing or difficulty breathing
    - swelling of the face, lips, tongue or other parts of the body
    - rash, itching or hives on the skin.
  • you are pregnant or think you may be pregnant.
  • you have previously had unprotected intercourse more than 72 hours earlier in the same menstrual cycle, as you may already be pregnant.
  • you are experiencing vaginal bleeding for which the reason is not known.
  • you have breast cancer.
  • the tablets do not look quite right.

Do not take this medicine after the expiry date printed on the pack or if the packaging is torn or shows signs of tampering.

If it has expired or is damaged, return it to your pharmacist for disposal.

If you are not sure whether you should start taking this medicine, talk to your doctor.

Before you start treatment with POSTRELLE-1, your doctor or pharmacist should:

  • discuss if you have allergies to any other medicines, foods, preservatives or dyes.
  • check you are not already pregnant if they suspect you may already have been pregnant before this occurrence of unprotected intercourse.
  • ask you if you are breast feeding.
  • ask you if you are taking any other medicines.
  • ask if you suffer from high blood pressure.
  • advise you of the need for careful use of a barrier method of contraception until you have your next period.
  • advise you to see your doctor in three weeks' time, especially if you have not had a period by then.
  • discuss the need for regular contraception.

You should consult with your doctor before you take POSTRELLE-1 if:

  • you have diabetes mellitus (with kidney, eye or nerve damage, or vascular disease). Diabetes mellitus is a condition in which the body does not produce enough insulin or else the body tissues are not able to use the insulin present. This leads to hyperglycaemia (too much sugar in the blood).
  • you have ischaemic heart disease (heart disease caused by reduced blood flow in the blood vessels of the heart muscle).
  • you have suffered a stroke.
  • you have had breast cancer.
  • are pregnant or think that you may already be pregnant. This medicine will not work if you are already pregnant. If you are already pregnant, POSTRELLE-1 cannot terminate pregnancy. POSTRELLE-1 is not an “abortion pill”. You may already be pregnant if:
    - your period is more than 5 days late, or you have experienced unusual bleeding when your next period is due.
    - you have had unprotected sex more than 72 hours ago and since your last period.

If any of these conditions apply to you, it may not be suitable for you to take POSTRELLE-1.

The use of POSTRELLE-1 is not advised if you:

  • have a disease of your gastrointestinal tract (such as Crohn's disease) that interferes with the digestion and absorption of your food and medicines.
  • have severe liver disease.
  • have a history of ectopic pregnancy (where the baby develops somewhere outside the womb).
  • have a history of salpingitis (inflammation of the fallopian tubes).
    A previous ectopic pregnancy or previous infection of the fallopian tubes increases the risk of a new ectopic pregnancy.
  • are vomiting or have severe diarrhoea.

Emergency contraception should be taken as soon as possible after unprotected intercourse.

You should only use POSTRELE-1 in emergencies and not as a regular method of contraception. If POSTRELLE-1 is used more than once in a menstrual cycle, it is less reliable and it is more likely to upset your menstrual cycle (period).

POSTRELLE-1 does not work as well as regular methods of contraception. Your doctor, practice nurse or family planning clinic can tell you about long-term methods of contraception which are more effective in preventing you from getting pregnant.

If you have not told your doctor or pharmacist about any of the above, tell them before you start taking POSTRELLE-1.

During treatment, you may be at risk of developing certain side effects. It is important you understand these risks and how to monitor for them. See additional information under Section 6. Are there any side effects?

Pregnancy and breastfeeding

Check with your doctor or pharmacist if you are pregnant or intend to become pregnant.

You should not take this medicine if you are already pregnant. If you do become pregnant even after taking this medicine, it is important that you see your doctor. Your doctor may want to check that the pregnancy is not ectopic (where the baby develops somewhere outside the womb). This is especially important if you develop severe abdominal pain after taking POSTRELLE-1, or if you have previously had an ectopic pregnancy, fallopian tube surgery, or pelvic inflammatory disease.

Talk to your doctor or pharmacist if you are breastfeeding or intend to breastfeed.

The active ingredient of this medicine is excreted into your breast milk. Therefore, it is suggested that you take your tablet immediately after breastfeeding and avoid nursing at least 3 days after taking this medicine.

Fertility

POSTRELLE-1 increases the possibility of menstruation disturbances which can sometimes lead to an earlier or later ovulation date resulting in a modified fertility date. Although there are no fertility data in the long term, after treatment with POSTRELLE-1, a rapid return to fertility is expected and therefore, regular contraception should be continued or initiated as soon as possible after POSTRELLE-1 use.

Children and adolescents

POSTRELLE-1 is not recommended for children. There is only limited information available on levonorgestrel when taken by women aged 14-16 years and no information on its use in younger women or children.

3. What if I am taking other medicines?

Tell your doctor or pharmacist if you are taking any other medicines, including any medicines, vitamins or supplements that you buy without a prescription from your pharmacy, supermarket or health food shop.

Some medicines may interfere with POSTRELLE-1 and affect how it works.

These include:

  • medicines used to treat epilepsy (for example, barbiturates, primidone, phenytoin, and carbamazepine).
  • medicines used to treat tuberculosis (for example, rifampicin, rifabutin).
  • medicines used to treat HIV infection (ritonavir, efavirenz).
  • a medicine used to treat fungal infections (griseofulvin).
  • herbal remedies containing St John's Wort (Hypericum perforatum).

POSTRELLE-1 may affect the way other medicines work. These include:

  • medicines used to prevent organ transplant rejection (ciclosporin).

These medicines may be affected by POSTRELLE-1 or may affect how well it works.

Your doctor and pharmacist have more information on medicines to be careful with or avoid while taking this medicine.

Check with your doctor or pharmacist if you are not sure about what medicines, vitamins or supplements you are taking and if these affect POSTRELLE-1.

4. How do I use POSTRELLE-1?

How much to take

  • Take 1 tablet as a single dose.
  • Swallow the tablet whole with a full glass of water. Do not chew.
    If you are already using a regular method of contraception such as the contraceptive pill, you can continue to take this at your regular time.
    Your doctor or pharmacist should advise you to use a barrier contraception method until your next period.
  • If you vomit within 2 hours of taking the tablet you should return to your pharmacy, doctor or clinic.
    You will need to take an additional tablet as the first one may not have been absorbed completely.

When to take POSTRELLE-1

  • POSTRELLE-1 should be used as soon as possible after unprotected intercourse and no later than 72 hours (3 days) after intercourse.
    The sooner that you take the tablet, the more effective the treatment is likely to be and the more likely that an unexpected pregnancy will be prevented. It is best to take it immediately after you receive it.
  • You should only take POSTRELLE-1 in emergencies and not as a regular method of contraception.
    If POSTRELLE-1 is used more than once in a menstrual cycle it is more likely to upset your menstrual cycle.
  • POSTRELLE-1 can be taken at any time in your menstrual cycle, assuming you are not already pregnant or think you may be pregnant.
  • If you are using one of the medicines that may prevent POSTRELLE-1 from working properly or if you have used one of these medicines in the past 4 weeks, POSTRELLE-1 may not work as well for you.
  • If you are already using a regular method of contraception, such as the contraceptive pill, you can continue to take this at your regular times.
  • If another unprotected intercourse takes place after the use of POSTRELLE-1 (also if this is during the same menstrual cycle), the tablet will not be effective and there is again the risk of pregnancy.

Follow all directions given to you by your doctor and pharmacist carefully.

They may differ for the information contained in this leaflet.

If you do not understand the instructions on the box, ask your doctor or pharmacist for help.

After taking POSTRELLE-1

  • After taking POSTRELLE-1, you should use other contraceptive methods if you want to have sex.
    POSTRELLE-1 won't prevent pregnancy from further unprotected sex. Your doctor or pharmacist should advise you to use a barrier contraception method until your next period.
  • You should see your doctor within 3 weeks of taking POSTRELLE-1.
    You may experience spotting or vaginal bleeding earlier than expected.
  • You must see your doctor if you do not get your period, it is more than 5 days late or your period is unusually light or unusually heavy.
    If POSTRELLE-1 does not work, you could be pregnant. Your doctor will order a pregnancy test.
    If you continue to use the contraceptive pill and you do not have a bleed in your pill-free week or while you are taking the non-hormonal tablets, you could be pregnant. Your doctor will order a pregnancy test.
  • You should see your doctor if you do become pregnant even after taking this medicine.
    There is no evidence that POSTRELLE-1 will harm a baby that develops in your uterus/womb, but your doctor may want to check for an ectopic pregnancy (where the baby develops somewhere outside the womb).
  • You must see your doctor immediately if you experience severe stomach pain.
    On rare occasions an ectopic or tubal pregnancy could occur. This is especially important if you have previously had an ectopic pregnancy, fallopian tube surgery or pelvic inflammatory disease.
  • You should discuss with your doctor other methods of long-term contraception.
    POSTRELLE-1 is only intended as an emergency measure. Discuss with your doctor other methods of long-term contraception which are more effective in preventing you from getting pregnant.
  • You should not breast feed within three days after taking POSTRELLE-1.
    Small amounts of levonorgestrel may appear in your breast milk.

If you use too much POSTRELLE-1

If you think that you have used too much POSTRELLE-1, you may need urgent medical attention.

You should immediately:

  • phone the Poisons Information Centre
    (Australia telephone 13 11 26) for advice, or
  • contact your doctor, or
  • go to the Emergency Department at your nearest hospital.

You should do this even if there are no signs of discomfort or poisoning.

Although there have been no reports of serious harmful effects from taking too many tablets at once, you may feel sick (vomit) or have vaginal bleeding. You should ask your pharmacist, doctor, practice nurse or family planning clinic for advice, especially if you have been sick, as the tablet may not have worked properly.

5. What should I know while using POSTRELLE-1?

Things you should do

Always follow your doctor's or pharmacist's instructions carefully.

Your doctor will be happy to discuss any questions you may have with your medication.

Remind any doctor, dentist or pharmacist you visit that you are using POSTRELLE-1.

Things you should not do

  • Do not give POSTRELLE-1 to anyone else.

Where to go for further information

If you require further information, you should contact your pharmacist, doctor or clinic.

Driving or using machines

Be careful before you drive or use any machines or tools until you know how POSTRELLE-1 affects you.

POSTRELLE-1 may cause dizziness or light-headedness in some people. Make sure you know how you react to POSTRELLE-1 before you drive a car, operate machinery or do anything else that could be dangerous.

Drinking alcohol

Tell your doctor or pharmacist if you drink alcohol.

Looking after your medicine

  • Keep your tablet in the original pack until you need to take it.
    If you take the tablet out of the pack it will not keep well.
  • Keep your tablet in a cool dry place where the temperature stays below 25°C.
    Do not take POSTRELLE-1 after the expiry date.
    The expiry date is printed on the pack and the blister foil.

Follow the instructions in the carton on how to take care of your medicine properly.

Store it in a cool dry place away from moisture, heat or sunlight; for example, do not store it:

  • in the bathroom or near a sink, or
  • in the car or on window sills.

Keep it where young children cannot reach it.

A locked cupboard at least one-and-a-half metres above the ground is a good place to store medicines.

Getting rid of any unwanted medicine

If you no longer need to use this medicine or it is out of date, take it to any pharmacy for safe disposal.

Do not use this medicine after the expiry date.

6. Are there any side effects?

All medicines can have side effects. If you do experience any side effects, most of them are minor and temporary. However, some side effects may need medical attention.

See the information below and, if you need to, ask your doctor or pharmacist if you have any further questions.

Less serious side effects

Less serious side effectsWhat to do
Gastrointestinal:
  • Nausea
  • Vomiting
  • Diarrhoea
General:
  • Tiredness
  • Headache
  • Dizziness
  • Tender breasts
Skin:
  • Skin reactions
Speak to your doctor or pharmacist if you have any of these less serious side effects and they worry you.

Serious side effects

Serious side effectsWhat to do
  • Stomach pain
  • Increased vaginal bleeding
Call your doctor straight away, or go straight to the Emergency Department at your nearest hospital if you notice any of these serious side effects.

Tell your doctor or pharmacist if you notice anything else that may be making you feel unwell.

Other side effects not listed here may occur in some people.

Reporting side effects

After you have received medical advice for any side effects you experience, you can report side effects to the Therapeutic Goods Administration online at www.tga.gov.au/reporting-problems. By reporting side effects, you can help provide more information on the safety of this medicine.

7. Product details

This medicine is available over-the-counter without a doctor's prescription.

What POSTRELLE-1 contains

Active ingredient
(main ingredient)		Levonorgestrel
Other ingredients
(inactive ingredients)		Povidone
Lactose monohydrate
Maize starch
Magnesium stearate
Silicon dioxide
Potential allergensContains sugars as lactose.

Do not take this medicine if you are allergic to any of these ingredients.

What POSTRELLE-1 looks like

POSTRELLE-1 is a round, white to off-white, uncoated flat tablet debossed '145' on one side and other side plain (AUST R 221973).

Who distributes POSTRELLE-1

Alphapharm Pty Ltd trading as Viatris
Level 1, 30 The Bond
30-34 Hickson Road
Millers Point NSW 2000
www.viatris.com.au
Phone: 1800 274 276

This leaflet was prepared in November 2024.

POSTRELLE®-1 is a Viatris company trade mark

POSTRELLE-1_cmi\Nov24/00

Published by MIMS January 2025

BRAND INFORMATION

Brand name

Postrelle-1

Active ingredient

Levonorgestrel

Schedule

S3

 

1 Name of Medicine

Levonorgestrel.

2 Qualitative and Quantitative Composition

Each Postrelle-1 tablet contains 1.5 mg of levonorgestrel.
Excipients with known effect: sugars as lactose monohydrate.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Postrelle-1 tablets.

Round, white to off-white, uncoated flat tablets debossed '145' on one side and other side plain.

4 Clinical Particulars

4.1 Therapeutic Indications

Postrelle-1 is an oral emergency contraceptive indicated for use within 72 hours of unprotected intercourse. It should be used only as an emergency measure. Women who present for repeated courses of emergency contraception should be advised to consider long-term methods of contraception.

4.2 Dose and Method of Administration

For oral administration.
One 1.5 mg tablet to be taken as soon as possible (and not later than 72 hours) after unprotected intercourse.
The highest efficacy is achieved if the tablet is taken as early as possible. Therefore, treatment should not be delayed as efficacy declines with time.
If the patient vomits within two hours of taking the tablet, she should return to her pharmacist, doctor or clinic where an additional tablet may be given.
Postrelle-1 can be used at any time during the menstrual cycle unless menstrual bleeding is overdue.

Children.

Postrelle-1 is not recommended in children.
Only limited data are available in young women of child-bearing potential aged 14-16 years. No data are available about use in young women aged less than 14 years or children.

4.3 Contraindications

Hypersensitivity to the active substance or to any of the excipients listed in Section 6.1 List of Excipients.
Postrelle-1 should not be given to pregnant women. If menstrual bleeding is overdue, if the last menstrual period was abnormal in timing or character or if pregnancy is suspected for any other reason, pregnancy should be excluded (by pregnancy testing or pelvic examination) before treatment is given.
If a woman has had unprotected intercourse more than 72 hours earlier in the same menstrual cycle, conception may have already occurred. Treatment with Postrelle-1 following the second act of intercourse may therefore be ineffective in preventing pregnancy. While the consensus is that levonorgestrel is not teratogenic, no guarantee can be given that pregnancy will result in a normal baby.
Progestogen-only contraceptive pills (POPs) are used as a routine method of birth control over longer periods of time, and are contraindicated in some conditions. It is not known whether these same conditions apply to the Postrelle-1 regimen consisting of the emergency use of one 1.5 mg tablet.
Traditionally many of the contraindications to combined hormonal contraception have been applied to progestogen-only contraception. Since the contraindications largely apply to oestrogen this is inappropriate. In their Medical Eligibility Criteria, The World Health Organisation advises that the only absolute contraindications to high dose progestogen-only contraception are unexplained vaginal bleeding, current breast cancer, pregnancy or hypersensitivity to any of the ingredients of the preparation.

4.4 Special Warnings and Precautions for Use

Conditions which are regarded as relative contraindications include severe hypertension (BP > 180+/110+), diabetes mellitus with nephropathy, retinopathy, neuropathy or vascular disease, ischaemic heart disease, stroke, or a past history of breast cancer. Since exposure to levonorgestrel with Postrelle-1 is brief, the risks of pregnancy in all women, including those with pre-existing medical conditions, are almost certainly greater than those associated with Postrelle-1. In individual cases the risk-benefit ratio should be assessed by the practitioner in discussion with the patient.
If pregnancy occurs or there are complaints of severe lower abdominal pain after treatment with levonorgestrel, the possibility of an ectopic pregnancy should be considered. The absolute risk of ectopic pregnancy is likely to be low, as levonorgestrel prevents ovulation and fertilisation. Ectopic pregnancy may continue, despite the occurrence of uterine bleeding. Therefore, levonorgestrel is not recommended for patients who are at risk of ectopic pregnancy (previous history of salpingitis or of ectopic pregnancy).
Repeated administration within a menstrual cycle is not advisable. Women who present for repeated courses of emergency contraception should be advised to consider long-term methods of contraception.
Emergency contraception should be taken as soon as possible after unprotected sexual intercourse or failure of a contraceptive method.

Use in hepatic impairment.

Postrelle-1 is not recommended in patients with severe hepatic dysfunction.

Excipients.

Postrelle-1 contains 154 mg lactose. This should be taken into account in women with rare hereditary problems of galactose intolerance, the total lactase deficiency or glucose-galactose malabsorption.

Regular methods of contraception.

Postrelle-1 is not as effective as conventional regular methods of contraception and is suitable only as an emergency measure. Emergency contraception does not prevent a pregnancy in every instance. If menstrual periods are delayed by more than 5 days or abnormal bleeding occurs at the expected date of menstrual periods or pregnancy is suspected for any other reason, pregnancy should be excluded.

Sexually transmitted diseases.

Levonorgestrel does not protect against sexually transmitted diseases (STDs), including HIV/AIDS.

Use in the elderly.

No data available.

Paediatric use.

Postrelle-1 is not indicated for use in children. Only limited data are available in young women of child-bearing potential aged 14 to 16 years. No data is available about use in young women aged less than 14 years or in children (also see Section 4.2 Dose and Method of Administration).

Effects on laboratory tests.

No data available.

Precautions before use.

Exclude pregnancy if suspected clinically.
Breast or pelvic examinations are not routinely necessary. Perform such examinations only if indicated by the patient's history.
Blood pressure may be measured before prescribing Postrelle-1. An elevated BP is not a contraindication to treatment but indicates the need for further investigation.
No routine laboratory testing is required.
Possibility of an early or late onset of the next menstrual period.
Advise the practice of abstinence or careful use of a barrier method (e.g. condom, diaphragm, spermicide, cervical cap) until the onset of the next period. Follow-up should be offered 3 weeks after administration of therapy to assess the effectiveness of the method, to discuss future management if a period has not occurred, and to counsel the patient about future contraception. The use of levonorgestrel does not affect the continuation or starting of regular hormonal contraception.
Women should be warned that if pregnancy occurs after treatment with Postrelle-1, there is a possibility of an ectopic pregnancy.

Precautions after use.

If pregnancy occurs after treatment with Postrelle-1, the possibility of an ectopic pregnancy should be considered.
Vomiting, severe diarrhoea or other causes of malabsorption, such as Crohn's disease, might impair the efficacy of Postrelle-1. Women suffering from conditions associated with possible malabsorption should be referred for medical consultation as consideration should be given to the taking of another tablet.
If the patient vomits within two hours of taking the tablet, she should return to her pharmacist, doctor or clinic where an additional tablet may be given (also see Section 4.2 Dose and Method of Administration).

4.5 Interactions with Other Medicines and Other Forms of Interactions

The metabolism of levonorgestrel can be enhanced by concomitant use of medicines which induce CYP3A4, one of the families of liver enzymes. This may reduce the effectiveness of Postrelle-1 in preventing pregnancy. Concomitant use of liver enzyme inducers like efavirenz, rifampin and medicinal products for epilepsy is not recommended.
Medicines suspected of having the capacity to reduce the efficacy of levonorgestrel containing medications include barbiturates (including primidone), phenytoin, carbamazepine, herbal medicines containing Hypericum perforatum (St John's wort), rifampicin, ritonavir, rifabutin, griseofulvin and efavirenz.
Medicines containing levonorgestrel may increase the risk of cyclosporin toxicity due to possible inhibition of cyclosporin metabolism.
Levonorgestrel has the ability to decrease glucose tolerance when it is used in the longer term. However, use of levonorgestrel as an emergency contraceptive is not thought to induce significant modification of carbohydrate metabolism.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

Levonorgestrel increases the possibility of cycle disturbances which can sometimes lead to earlier or later ovulation dates. These changes can result in modified fertility dates; however, there are no long term fertility data.
(Category D)
Postrelle-1 is not to be used during an existing or suspected pregnancy. Research has found no significant effects on fetal development associated with the long-term use of contraceptive doses of combined oral steroids before pregnancy or taken inadvertently during early pregnancy. There have been an insufficient number of pregnancies in patients using levonorgestrel-only oral contraceptives to rigorously evaluate the potential for developmental toxicity; however, based on the combined oral contraceptive experience, an increase in abnormalities is not expected. If taken by the mother at or after 8 weeks post-conception, progestogens such as levonorgestrel can cause virilisation of the female fetus. This is a dose dependent effect. Prior to 8 weeks post-conception, they have no virilising effects. There are no studies of the effect of the high levonorgestrel doses used in Postrelle-1 on pregnancy and embryo/fetal development.
 Progestogens do not appear to affect the quantity or quality of breast milk. However, levonorgestrel has been identified in the breast milk following oral administration to lactating women. Women should be advised not to breast-feed within 3 days after taking Postrelle-1.

4.7 Effects on Ability to Drive and Use Machines

The effects of this medicine on a person's ability to drive and use machines were not assessed as part of its registration.

4.8 Adverse Effects (Undesirable Effects)

Clinical trial data.

The adverse events reported with an incidence of greater than 1% in the Ho and Kwan and the Pivotal Studies (two 750 microgram tablets taken 12 hours apart) are included in Table 1.
Side effects did not result in any discontinuations in either study. No ectopic pregnancies or congenital abnormalities were reported in either study. However, such a possibility must always be considered, as there have been rare reports of ectopic pregnancies reported during post-marketing surveillance. Cutaneous reactions have also been reported from post-marketing surveillance on rare occasions.
In the additional studies conducted to compare dosing with two 750 microgram tablets taken as a single dose and taking the two tablets 12 hours apart, the adverse events recorded were mostly similar to the above studies, as detailed in Table 2.
One ectopic pregnancy was observed in the pivotal study and none in the supporting (Arowojolu) study.
Overall, there was no indication that taking the full 1.5 mg dose at the one time resulted in an adverse event profile of greater concern than that for the regimen when the two 750 microgram tablets were taken 12 hours apart.
From post-marketing surveillance the following adverse events have been reported:

Skin and subcutaneous tissue disorders.

Very rare (< 1/10,000): rash, urticaria, pruritus.

Reproductive system and breast disorders.

Very rare (< 1/10,000): pelvic pain, dysmenorrhoea.

Gastrointestinal disorders.

Very rare (< 1/10,000): abdominal pain.

General disorders and administration site conditions.

Very rare (< 1/10,000): face oedema.

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at www.tga.gov.au/reporting-problems.

4.9 Overdose

For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).
Serious ill effects have not been reported following acute ingestion of large doses of oral contraceptives. Overdose may cause nausea and vomiting, and withdrawal bleeding may occur. There are no specific antidotes and treatment should be symptomatic.

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Postrelle-1 is an emergency oral contraceptive tablet containing the synthetic progestogen, levonorgestrel.
The precise mode of action of levonorgestrel is not known. Emergency hormonal contraception is thought to work mainly by preventing ovulation and fertilisation by altering tubal transport of sperm and/or ova. Levonorgestrel is not effective once the process of implantation has begun.

Clinical trials.

Two large controlled studies of levonorgestrel using 750 microgram tablets (two tablets taken 12 hours apart), for emergency contraception have been undertaken. The first of these is referred to as the Ho and Kwan study and the second, which included larger numbers, as the Pivotal study. Both studies compared this treatment regime to the Yuzpe regimen (ethinylestradiol 100 micrograms plus levonorgestrel 500 micrograms, repeated 12 hours later).
The Ho and Kwan study was a single centre and open-label (age range 18-45 years) while the Pivotal study was multicentre, randomised and double-blind (age range 14-47 years), with both including women requiring emergency contraception resulting from no contraception used during intercourse or contraception method failure. The regimens were similar with two exceptions:
The Ho and Kwan study allowed treatment to be initiated up to 48 hours post-intercourse whereas the Pivotal study allowed a 72 hour gap between treatment initiation and intercourse.
The treatment regimen in both studies used two tablets, the second taken 12 hours after the first. In the Pivotal study only, women in each of the two groups were provided with replacement medication to take should vomiting occur within four hours of either dose.
The efficacy results from the efficacy population analysis from the two studies are summarised in Table 3:
The relative risk of pregnancy in the Pivotal study for the Yuzpe versus levonorgestrel regimens was 2.8 with a lower one-sided 95% confidence bound of 1.53.
Stratified analyses of the data showed no significant effect for age or ethnicity. For intervals between intercourse and initiation of treatment, shorter intervals were associated with lower pregnancy rates.
Two further studies have been conducted in order to determine whether taking two 750 microgram tablets at the same time (as a single dose) was as efficacious as taking the two tablets 12 hours apart.
The pivotal study for this comparison was a double blind, randomised, double dummy multicentre study, conducted by the WHO/HRP across 10 countries. This study included women ranging in age from 14 to 52 years, and allowed for enrolment up to 120 hours after intercourse.
A supporting study (Arowojolu et al, 2002) for this comparison was conducted in Nigeria at a single centre. A total of 1118 women were assessed for efficacy in this study.
The efficacy results from the data analysis for the two treatment regimens from both studies are summarised in Table 4:
There was no significant difference in efficacy between the two levonorgestrel treatment groups in the pivotal study. Shorter intervals between intercourse and treatment were associated with lower pregnancy rates in both groups.
The authors of the supporting study (Arowojolu et al, 2002) concluded that both treatment regimens were effective - the single two tablet dose appeared to be more effective than when the two tablets were taken 12 hours apart and that the earlier the medication is taken after unprotected intercourse, the better the efficacy.
Adverse events reported in these two studies were similar for both treatment groups (see Section 4.8 Adverse Effects (Undesirable Effects)).
No specific clinical trials investigating pregnancy outcome have been conducted on the single 1.5 mg tablet. Evidence for its efficacy is based on the 1.5 mg tablet and two 750 microgram tablets taken at the same time having the same pharmacokinetic profile.

Efficacy.

From earlier studies where two levonorgestrel tablets (each 750 micrograms) have been taken 12 hours apart, it has been estimated that levonorgestrel prevents 85% of expected pregnancies. Efficacy appears to decline with time after intercourse (95% within 24 hours, 85% 24-48 hours, 58% if used between 48 and 72 hours).
In an additional study to compare taking the two tablets 12 hours apart versus taking a total dose of 1.5 mg after unprotected intercourse, similar rates of prevention of pregnancy were observed when taken within 72 hours. In this study, it was also observed that efficacy declined with increasing time of taking the medication after intercourse.
In further studies to compare the bioavailability of the single 1.5 mg tablet to two 750 microgram tablets, it has been determined that the efficacy would be similar.

5.2 Pharmacokinetic Properties

Absorption.

A study compared the pharmacokinetics of a 1.5 mg levonorgestrel tablet taken as a single dose with that of two 750 microgram tablets taken 12 hours apart. Following ingestion of one 1.5 mg tablet, maximum plasma drug levels of 18.5 nanogram/mL were found at 2 hours. Thereafter, levonorgestrel plasma levels decreased with a half life of approximately 26 hours. In this study, the Cmax was higher for the single 1.5 mg tablet, but plasma levels over a 24 hour period were similar, as were the Tmax and half life.
In another study, a comparison of the pharmacokinetics with two 750 microgram tablets taken together (as a single dose) or 12 hours apart showed similar levels of serum levonorgestrel over a 24 hour period, and similar terminal half lives (43.7 versus 43.3 hours). The Cmax was about 50% higher when the two tablets were taken together than when they were taken 12 hours apart (12.3 versus 7.9 nanogram/mL, p=0.03), and this occurred at 2.5 and 1.8 hours, respectively, after the (first) dose.
When the bioavailability of a single 1.5 mg levonorgestrel tablet was compared to two 750 microgram tablets taken at the same time, AUC and Cmax were found to be the same with both treatments. In this study, maximum plasma drug levels of 19.1 nanogram/mL were found at 1.7 hours following the ingestion of one 1.5 mg tablet. Thereafter, levonorgestrel plasma levels decreased with a half life of approximately 27 hours.
In general, it is recognised that the pharmacokinetics of levonorgestrel can be quite variable.

Distribution.

Levonorgestrel is bound to serum albumin and sex hormone binding globulin (SHBG). Only about 1.5% of the total serum levels are present as free steroid, but 65% are specifically bound to SHBG.

Metabolism and excretion.

Levonorgestrel is not excreted in unchanged form but as metabolites. Levonorgestrel metabolites are excreted in about equal proportions in urine and faeces. The biotransformation follows the known pathways of steroid metabolism with levonorgestrel being hydroxylated in the liver and the metabolites then excreted as glucuronide conjugates. No pharmacologically active metabolites are known.
The absolute bioavailability of levonorgestrel was determined to be almost 100% of the dose administered.
About 0.1% of the maternal dose can be transferred via milk to the breast-fed infant.

5.3 Preclinical Safety Data

Genotoxicity.

No studies of the mutagenic potential of levonorgestrel have been performed.

Carcinogenicity.

No studies of the carcinogenic potential of levonorgestrel have been performed. Numerous epidemiological studies have been performed to determine the incidence of breast, endometrial, ovarian and cervical cancer in women using combination oral contraceptives. Some studies suggest that combination oral contraceptive use has been associated with an increase in the risk of cervical intraepithelial neoplasia in some populations of women but there continues to be controversy about the extent to which this finding is attributable to the confounding effects of sexual behaviour and other factors such as human papilloma virus (HPV). Evidence in the literature suggests that use of combination oral contraceptives is not associated with an increased risk of developing breast cancer in the overall population of users. However, some of these same studies have shown an increased relative risk of breast cancer in certain subgroups of combination oral contraceptive users, although no consistent pattern of findings has been identified. Benign hepatic adenomas have been found to be associated with the use of oral contraceptives containing levonorgestrel. Although benign, hepatic adenomas may rupture and cause death through intra-abdominal haemorrhage. The contribution of the progestin component of oral contraceptives to the development of hepatic adenomas is not known.

6 Pharmaceutical Particulars

6.1 List of Excipients

Povidone, lactose monohydrate, maize starch, magnesium stearate and silicon dioxide.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Store below 25°C. Do not remove from the primary pack except immediately before use.

6.5 Nature and Contents of Container

Container type: blister pack (PVC/PVDC/Aluminium).
Pack size: 1 tablet.

Australian register of therapeutic goods (ARTG).

AUST R 221973 - Postrelle-1 levonorgestrel 1.5 mg tablet blister pack.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking it to your local pharmacy.

6.7 Physicochemical Properties

Chemical structure.

Chemical name: (-)-13β- ethyl-17β-hydroxy-18,19-dinor-17α-pregn-4-en-20-yn-3-one.
Structural formula:
Molecular formula: C21H28O2.
Molecular weight: 312.45.
Levonorgestrel is a white or almost white, odourless or almost odourless, crystalline powder. Practically insoluble in water; slightly soluble in alcohol, in acetone, and in ether; soluble in chloroform; sparingly soluble in methylene chloride.

CAS number.

797-63-7.

7 Medicine Schedule (Poisons Standard)

S3 - Pharmacist Only Medicine.

Summary Table of Changes