SUMMARY CMI

PTU™ 50 mg Tablets

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 PTU™ 50 mg Tablets?

PTU contains the active ingredient propylthiouracil. PTU is used to treat an overactive thyroid gland.

For more information, see Section 1. Why am I using PTU™ 50 mg Tablets? in the full CMI.

2. What should I know before I use PTU™ 50 mg Tablets?

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

Talk to your doctor 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 PTU™ 50 mg Tablets? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with PTU 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 PTU™ 50 mg Tablets?

• Your doctor will tell you how many tablets to take, and when to take them each day.
• Follow all directions given to you by your doctor or pharmacist carefully.
• If you do not understand the instructions on the bottle, ask your doctor or pharmacist for help.

More instructions can be found in Section 4. How do I use PTU™ 50 mg Tablets? in the full CMI.

5. What should I know while using PTU™ 50 mg Tablets?

For more information, see Section 5. What should I know while using PTU™ 50 mg Tablets? in the full CMI.

6. Are there any side effects?

Common side effects include itching, dizziness, joint pain, taste loss, nausea, vomiting, stomach pain, numbness or tingling of fingers, toes, or face, skin rash, skin or hair colour change, hair loss and sore, red or watery eyes. Serious side effects include yellow eyes and skin, hearing loss, swollen glands, unusual bleeding or bruising, increase or decrease in urination, backache, feet or lower legs swelling, joint pain, fever, skin rash or raised red lumps, wheezing or difficulty breathing, difficulty passing urine, hives, upper abdominal pain, tingling or pricking feeling, mouth ulcers and bleeding or bruising more easily than normal.

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

PTU™ 50 mg Tablets

Active ingredient: Propylthiouracil

Consumer Medicine Information (CMI)

This leaflet provides important information about using PTU. 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 PTU.

Where to find information in this leaflet:

1. Why am I using PTU™ 50 mg Tablets?
2. What should I know before I use PTU™ 50 mg Tablets?
3. What if I am taking other medicines?
4. How do I use PTU™ 50 mg Tablets?
5. What should I know while using PTU™ 50 mg Tablets?
6. Are there any side effects?
7. Product details

1. Why am I using PTU™ 50 mg Tablets?

PTU contains the active ingredient propylthiouracil. PTU belongs to a group of medicines called antithyroid medicines

PTU is used to treat an overactive thyroid gland.

An overactive thyroid gland produces too much thyroid hormones, also known as hyperthyroidism. This medicine may also be used to treat symptoms of hyperthyroidism before surgery or radioactive iodine therapy.

This medicine works by stopping thyroid hormone from forming. This medicine may take up to a week to reduce the symptoms of hyperthyroidism.

Ask your doctor if you have any questions about why this medicine has been prescribed for you.

Your doctor may have prescribed it for another reason.

2. What should I know before I use PTU™ 50 mg Tablets?

Warnings

Do not use PTU if:

• you are allergic to propylthiouracil, or any of the ingredients listed at the end of this leaflet. Always check the ingredients to make sure you can use this medicine.
• you are allergic to any other similar medicines called thioamide derivatives.

Check with your doctor if you have or have had:

• asthma
• allergies to any other medicines, foods, preservatives, or dyes

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 if you are pregnant or intend to become pregnant.

PTU has caused, is suspected to have caused or may be expected to cause an increased incidence of human fetal malformations or irreversible damage.

Do not breastfeed if you are taking this medicine.

Talk to your doctor if you are breastfeeding or intend to breastfeed. The active ingredient in PTU passes into breast milk and there is a possibility that your baby may be affected.

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 PTU and affect how it works.

These include:

• medicines used to prevent blood clots or thin the blood, for example, heparin, warfarin, aspirin
• any medications which have a side effect called agranulocytosis, a lack of white blood cells. These include sulfonamide antibiotics, clozapine (a medicine used to treat schizophrenia) and spironolactone (a medicine used to treat hypertension). Ask your doctor for more information on the medicines that cause this side effect.

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

4. How do I use PTU™ 50 mg Tablets?

How much to take

• Your doctor will tell you how many tablets to take, and when to take them each day.
• Follow the instructions provided and use PTU until your doctor tells you to stop.
• If you do not understand the instructions on the bottle, ask your doctor or pharmacist for help.

When to take PTU™ 50 mg Tablets

• PTU must be taken every day in equal doses at equal intervals during the day. If your doctor tells you to take 2 doses per day you would take each dose 12 hours apart. If your doctor tells you to take 4 doses per day you would take each dose 6 hours apart.
• Take your medicine at about the same time each day.
  Taking it at the same time each day will have the best effect. It will also help you remember when to take it.
• Continue taking your medicine for as long as your doctor tells you to.

How to take PTU™ 50 mg Tablets

Swallow the tablets whole with a full glass of water.

If you forget to use PTU™ 50 mg Tablets

If it is less than 6 hours for a twice-daily dose or 3 hours for a four times daily dose before your next dose, skip the dose you missed and take your next dose when you are meant to.

Otherwise, take it as soon as you remember, and then go back to taking your medicine as you would normally.

Do not take a double dose to make up for the dose you missed.

If you have trouble remembering to take your medicine or not sure what to do, ask your doctor or pharmacist for some hints.

If you use too much PTU™ 50 mg Tablets

If you think that you have used too much PTU, you may need urgent medical attention.

You should immediately:

• phone the Poisons Information Centre
  (by calling 13 11 26), 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.

5. What should I know while using PTU™ 50 mg Tablets?

Things you should do

If you are about to be started on any new medicine, remind your doctor and pharmacist that you are taking PTU.

Tell any other doctors, dentists, pharmacists and nurses who treat you that you are taking PTU.

If you are going to have surgery, tell the surgeon or anaesthetist that you are taking PTU. It may affect other medicines used during surgery.

If you are about to have any blood tests, tell your doctor that you are taking PTU.

Call your doctor straight away if you:

• become pregnant during the course of PTU treatment.

Remind any doctor, dentist, pharmacist or nurse you visit that you are using PTU.

Things you should not do

• Do not stop using this medicine suddenly.
• Do not take PTU to treat any other complaints unless your doctor tells you to.
• Do not give your medicine to anyone else, even if they have the same condition as you.
• Do not stop taking your medicine or lower the dosage without checking with your doctor.

Driving or using machines

Be careful before you drive or use any machines or tools until you know how PTU affects you.

PTU may cause dizziness and/or tiredness in some people. If you have any of these symptoms, do not drive, operate machinery or do anything else that could be dangerous.

Things to be careful of

Children should be careful when riding bicycles or climbing trees.

If you feel light-headed, dizzy or faint when getting out of bed or standing up, get up slowly.

Looking after your medicine

• Keep your tablets in the bottle until it is time to take them.
• Store below 30°C.

Follow the instructions on the bottle 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.

When to discard your medicine

If your doctor tells you to stop taking this medicine or the expiry date has passed, ask your pharmacist what to do with any medicine that is left over.

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 about side effects.

Less serious side effects

Less serious side effects (meaning PTU is not working the way it should)

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.

Always make sure you speak to your doctor or pharmacist before you decide to stop taking any of your medicines.

7. Product details

This medicine is only available with a doctor's prescription.

What PTU™ 50 mg Tablet contains

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

What PTU™ 50 mg Tablet looks like

PTU tablet is round, white and biconvex. One side is debossed with “PRESTAB” while the other side is plain (AUST R 13319).

Who distributes PTU™ 50 mg Tablets

PTU is supplied in Australia by:

Phebra Pty Ltd
19 Orion Road, Lane Cove West,
NSW 2066, Australia
Telephone: 1800 720 020

This leaflet was prepared in July 2021.

PTU, Phebra and the Phi symbol are trademarks of Phebra Pty Ltd, 19 Orion Road, Lane Cove West, NSW 2066, Australia.

Published by MIMS September 2021

1 Name of Medicine

Propylthiouracil.

2 Qualitative and Quantitative Composition

Propylthiouracil is a thioamide derivative which occurs as a white crystalline powder, odourless with a bitter taste, very slightly soluble in water, sparingly soluble in ethanol and soluble in solutions of alkali hydroxides or ammonia.
PTU 50 mg Tablets contain 50 mg of the active ingredient propylthiouracil.

Excipients with known effect.

3 Pharmaceutical Form

PTU 50 mg Tablets are white, round, biconvex and uncoated. One side is debossed 'PRESTAB' and other side is plain.

4 Clinical Particulars

4.1 Therapeutic Indications

Propylthiouracil is an antithyroid drug indicated for the total treatment of hyperthyroidism or in the treatment of the thyrotoxic patient prior to surgery or radioactive iodine therapy.

4.2 Dose and Method of Administration

Propylthiouracil is administered orally, usually in 2 to 4 equal doses at 12 to 6 hourly intervals respectively.

Dosage in adults.

Maintenance dose.

Thyrotoxic crisis.

Dosage in children.

Initial.

6-10 years.

10 years and over.

Maintenance dose.

4.3 Contraindications

Patients who are known to be hypersensitive to propylthiouracil or related thioamide derivatives.

4.4 Special Warnings and Precautions for Use

In preparing patients for surgery, the administration of iodine is recommended concomitantly with propylthiouracil to decrease the vascularity and friability of the thyroid gland.
Although propylthiouracil is used for the total treatment of hyperthyroidism, duration of treatment necessary to produce a prolonged remission varies from 6 months to several years, with an average duration of one year. Remission has occurred in at least 50% of patients 6-12 months after cessation of medication.
In view of the fact that hypothyroid patients seem to have poor adrenergic nervous function, use with caution in patients with asthma.
Patients should be closely supervised during prolonged propylthiouracil therapy because of the likelihood of agranulocytosis. Patients should be warned to report immediately any evidence of illness, particularly sore throat, skin eruptions, fever, chills, headache, and malaise.
All patients receiving propylthiouracil should have regular full blood counts as well as close monitoring of liver and thyroid function tests (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions; Section 4.8 Adverse Effects (Undesirable Effects)).
Regular thyroid function tests are recommended in patient monitoring (recommended prior to initiation of therapy, at monthly intervals during stabilization, then every 2 to 3 months), viz free (unbound) serum thyroxine (T₄) levels, total serum T₄ levels, serum thyrotropin (TSH), total serum triiodothyronine (T₃). Liver function tests are also recommended at periodic intervals during therapy.

Hepatotoxicity.

Agranulocytosis producing medications.

Use in the elderly.

Paediatric use.

Effects on laboratory tests.

4.5 Interactions with Other Medicines and Other Forms of Interactions

Because propylthiouracil can cause hypoprothrombinemia, extreme caution is advised in patients receiving oral anticoagulants or heparin. Prothrombin times should be carefully monitored during therapy.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

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)

Note.

Incidence more frequent.

Incidence less frequent.

Incidence rare.

Signs of overdosage or hypothyroidism.

Signs of thyrotoxicosis or inadequate therapy.

Hepatotoxicity.

Vasculitis.

Reporting suspected adverse effects.

4.9 Overdose

Agranulocytosis is the most serious adverse effect resulting from overdose and/or prolonged administration. Hypothyroidism may result from prolonged therapy (see Section 4.8 Adverse Effects (Undesirable Effects)).
General management of overdosage may consist of gastric lavage, observation, and symptomatic and supportive therapy.
Treatment is directed at the specific adverse effect e.g. in bone marrow depression, treatment by way of blood transfusion of fresh whole blood, antibiotics, and corticosteroids are used. Prothrombin deficiency associated with a haemorrhagic diathesis may be counteracted by phytomenadione.
For information on the management of overdose, contact the Poisons Information Centre on 131126 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Clinical trials.

5.2 Pharmacokinetic Properties

Absorption.

Distribution.

Metabolism.

Excretion.

5.3 Preclinical Safety Data

Genotoxicity.

Carcinogenicity.

6 Pharmaceutical Particulars

6.1 List of Excipients

The inactive ingredients are lactose monohydrate, magnesium stearate, povidone, sodium lauryl sulfate and maize starch.

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 30°C.

6.5 Nature and Contents of Container

PTU 50 mg Tablets are supplied in bottles containing 100 tablets.
AUST R 13319.
Phebra Product Code - TAB001.

6.6 Special Precautions for Disposal

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

6.7 Physicochemical Properties

Chemical name: 1,2-dihydro-6- propyl-2- thioxopyrimidine-4-one.
The molecular weight of the compound is 170.2, the molecular formula is C₇H₁₀N₂OS.

Chemical structure.

CAS number.

7 Medicine Schedule (Poisons Standard)

Schedule 4 - Prescription Only Medicine.

Summary Table of Changes