Consumer medicine information

DBL Dobutamine Hydrochloride Injection

Dobutamine

BRAND INFORMATION

Brand name

DBL Dobutamine Hydrochloride Injection

Active ingredient

Dobutamine

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using DBL Dobutamine Hydrochloride Injection.

SUMMARY CMI

DBL™ Dobutamine Hydrochloride Injection

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 being treated with DBL Dobutamine Hydrochloride Injection?

DBL Dobutamine Hydrochloride Injection contains the active ingredient dobutamine hydrochloride. DBL Dobutamine Hydrochloride Injection is used in patients who require short-term treatment of heart failure following a heart attack or heart surgery.

For more information, see Section 1. Why am I being treated with DBL Dobutamine Hydrochloride Injection? in the full CMI.

2. What should I know before treatment with DBL Dobutamine Hydrochloride Injection?

Do not use if you have ever had an allergic reaction to dobutamine hydrochloride, sodium metabisulfite or any of the other 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 treatment with DBL Dobutamine Hydrochloride Injection? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with DBL Dobutamine Hydrochloride Injection 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 is DBL Dobutamine Hydrochloride Injection given?

Your doctor will decide what dose of dobutamine you will receive. This depends on your condition and other factors, such as your weight.

DBL Dobutamine Hydrochloride Injection is given to you by a doctor or nurse as a slow injection into a vein (via a ‘drip’).

More instructions can be found in Section 4. How is DBL Dobutamine Hydrochloride Injection given? in the full CMI.

5. What should I know during treatment with DBL Dobutamine Hydrochloride Injection?

Things you should do
  • Remind any doctor, nurse, pharmacist or dentist you visit that you were or are being treated with DBL Dobutamine Hydrochloride Injection.
Driving or using machines
  • Be careful before you drive or use any machines or tools until you know how DBL Dobutamine Hydrochloride Injection affects you.

For more information, see Section 5. What should I know during treatment with DBL Dobutamine Hydrochloride Injection? in the full CMI.

6. Are there any side effects?

Side effects include: nausea and vomiting, and headache. Serious side effects include: pain or tenderness at the injection site, allergic reaction symptoms (which 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), fast or irregular heart beat, chest pain (such as angina pain), shortness of breath, tremors or shaking, and feeling anxious or nervous.

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

DBL™ Dobutamine Hydrochloride Injection

Active ingredient(s): Dobutamine Hydrochloride (do-BEWT-a-meen)

Consumer Medicine Information (CMI)

This leaflet provides important information about using DBL Dobutamine Hydrochloride Injection. You should also speak to your doctor or pharmacist if you would like further information or if you have any concerns or questions about being treated with DBL Dobutamine Hydrochloride Injection.

Where to find information in this leaflet:

1. Why am I being treated with DBL Dobutamine Hydrochloride Injection?
2. What should I know before treatment with DBL Dobutamine Hydrochloride Injection?
3. What if I am taking other medicines?
4. How is DBL Dobutamine Hydrochloride Injection given?
5. What should I know during treatment with DBL Dobutamine Hydrochloride Injection?
6. Are there any side effects?
7. Product details

1. Why am I being treated with DBL Dobutamine Hydrochloride Injection?

DBL Dobutamine Hydrochloride Injection contains the active ingredient dobutamine hydrochloride.

DBL Dobutamine Hydrochloride Injection is used in patients who require short-term treatment of heart failure following a heart attack or heart surgery.

DBL Dobutamine Hydrochloride Injection acts directly on the heart muscle to increase the force of each contraction.

Your doctor may have prescribed this medicine for another reason.

Ask your doctor if you have any questions about why DBL Dobutamine Hydrochloride Injection has been prescribed for you.

There is no evidence that DBL Dobutamine Hydrochloride Injection is addictive.

2. What should I know before treatment with DBL Dobutamine Hydrochloride Injection?

Warnings

You must not be given DBL Dobutamine Hydrochloride Injection if:

  1. you are allergic to dobutamine hydrochloride, sodium metabisulfite or any of the other ingredients listed at the end of this leaflet.
Symptoms of an allergic reaction to DBL Dobutamine Hydrochloride Injection 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.
Always check the ingredients to make sure you can use this medicine.
  1. you have a heart condition called idiopathic hypertrophic subaortic stenosis (a narrowing of an artery coming from the heart).

If you are not sure whether you should be given DBL Dobutamine Hydrochloride Injection, talk to your doctor or pharmacist.

Check with your doctor if you:

  • have allergies to:
    - any other medicines
    - any other substances, such as foods, preservatives or dyes.
  • have or have had any other medical conditions, especially the following:
    - high blood pressure
    - fast or irregular heart beat
    - other heart problems
    - low potassium levels (hypokalaemia)
  • take any medicines for any other condition

If you have not told your doctor or pharmacist about any of the above, tell them before you start being treated with DBL Dobutamine Hydrochloride Injection.

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.

DBL Dobutamine Hydrochloride Injection is not recommended for use during pregnancy. If there is a need to consider dobutamine during pregnancy, your doctor will discuss with you the benefits and risks of being given it.

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

You should not breastfeed while being given DBL Dobutamine Hydrochloride Injection.

Use in Children

DBL Dobutamine Hydrochloride Injection is not recommended in children as the safety and effectiveness of dobutamine in children have not been established.

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 DBL Dobutamine Hydrochloride Injection and affect how it works.

These include:

  • some general anaesthetics, such as halothane
  • beta-blockers, a type of medication used for heart and blood pressure problems.
  • entacapone, a medicine used for Parkinson's disease
  • glyceryl trinitrate, a medicine used for angina.

These medicines may be affected by DBL Dobutamine Hydrochloride Injection, or may affect how well it works. You may need different amounts of your medicine, or you may need to take or use different medicines. Your doctor or pharmacist will advise you.

Your doctor and pharmacist may have more information on medicines to be careful with or avoid while being treated with DBL Dobutamine Hydrochloride Injection.

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

4. How is DBL Dobutamine Hydrochloride Injection given?

How much is given

Your doctor will decide what dose of dobutamine you will receive. This depends on your condition and other factors, such as your weight.

How is it given

DBL Dobutamine Hydrochloride Injection is given as a slow injection into a vein (via a ‘drip’). It must only be given by a doctor or nurse.

If you are given too much DBL Dobutamine Hydrochloride Injection

As DBL Dobutamine Hydrochloride Injection is given to you under the supervision of your doctor, it is very unlikely that you will receive too much.

If you think that you have been given too much DBL Dobutamine Hydrochloride Injection, you may need urgent medical attention.

You should immediately:

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

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

Symptoms of a dobutamine overdose include the side effects listed below in Section 6. Are there any side effects? but are usually of a more severe nature.

5. What should I know during treatment with DBL Dobutamine Hydrochloride Injection?

Things you should do

Remind any doctor, nurse, pharmacist or dentist you visit that you were or are being treated with DBL Dobutamine Hydrochloride Injection.

Driving or using machines

Be careful before you drive or use any machines or tools until you know how DBL Dobutamine Hydrochloride Injection affects you.

Drinking alcohol

Tell your doctor if you drink alcohol.

6. Are there any side effects?

Tell your doctor or pharmacist as soon as possible if you do not feel well while you are being given DBL Dobutamine Hydrochloride Injection.

It helps most people with heart failure, but it may have unwanted side effects in a few people. 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.

Side effects

Side effectsWhat to do
General
  • nausea and vomiting
  • headache
  • fever
Administration site conditions
  • pain or tenderness at the injection site
Speak to your doctor, nurse or pharmacist if you have any of these side effects and they worry you.

Serious side effects

Serious side effectsWhat to do
Allergic reaction symptoms

This includes:

  • 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.
  • itchy scalp (pruritus)
Heart related
  • fast or irregular heart beat
  • chest pain (such as angina pain)
Respiratory related
  • shortness of breath
Nervous system related
  • tremors or shaking
Changes in behaviour, thinking or mood
  • feeling anxious or nervous
Call your doctor, nurse or pharmacist 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.

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 DBL Dobutamine Hydrochloride Injection contains

Active ingredient
(main ingredient)		dobutamine hydrochloride
Other ingredients
(inactive ingredients)

sodium metabisulfite

water for injections

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

DBL Dobutamine Hydrochloride Injection does not contain lactose, sucrose, gluten, tartrazine or any other azo dyes.

What DBL Dobutamine Hydrochloride Injection looks like

DBL Dobutamine Hydrochloride Injection is a clear, colourless or slightly yellow solution. (Aust R 46451).

DBL Dobutamine Hydrochloride Injection is supplied as 250 mg/20 mL vials.

How is DBL Dobutamine Hydrochloride Injection stored

DBL Dobutamine Hydrochloride Injection will be stored in the pharmacy or on the ward. The injection is kept in a cool dry place, protected from light, where the temperature stays below 25°C.

Who distributes DBL Dobutamine Hydrochloride Injection

Pfizer Australia Pty Ltd
Sydney NSW
Toll Free Number: 1800 675 229
www.pfizermedicalinformation.com.au

This leaflet was prepared in August 2022.

Published by MIMS September 2022

BRAND INFORMATION

Brand name

DBL Dobutamine Hydrochloride Injection

Active ingredient

Dobutamine

Schedule

S4

 

1 Name of Medicine

Dobutamine hydrochloride.

2 Qualitative and Quantitative Composition

Each 20 mL vial of DBL Dobutamine Hydrochloride Injection contains dobutamine hydrochloride 280.2 mg (250 mg dobutamine equivalent) and sodium metabisulfite 4.4 mg.
Dobutamine hydrochloride is a white to practically white, crystalline powder. It is sparingly soluble in water and methyl alcohol; soluble in alcohol.

Excipient with known effect.

Sodium metabisulfite.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Solution for injection.
DBL Dobutamine Hydrochloride Injection is a sterile solution.

4 Clinical Particulars

4.1 Therapeutic Indications

DBL Dobutamine Hydrochloride Injection is indicated in adults who require short-term treatment of cardiac failure secondary to acute myocardial infarction, or cardiac surgery.

4.2 Dose and Method of Administration

Dosage.

The rate of infusion needed to increase cardiac output usually ranges from 2.5 to 10 microgram/kg/min (see Table 1). On rare occasions, infusion rates up to 40 microgram/kg/min have been required to obtain the desired effect. However, the possibility of intensifying myocardial ischaemia should be borne in mind and the lowest effective dose infused.
The rate of administration and the duration of therapy should be adjusted according to the patient's response, as determined by heart rate, presence of ectopic activity, blood pressure, urine flow, and, whenever possible, measurement of central venous or pulmonary wedge pressure and cardiac output.
Concentrations up to 5,000 microgram/mL have been administered to humans (250 mg/50 mL). The final volume administered should be determined by the fluid requirements of the patient.

Method of administration.

DBL Dobutamine Hydrochloride Injection must be diluted to at least 50 mL at the time of administration in 5% glucose injection or 0.9% sodium chloride injection. Although chemically stable for 24 hours, prepared solutions should be used immediately after dilution.
Do not add DBL Dobutamine Hydrochloride Injection to 5% sodium bicarbonate injection or any other strongly alkaline solutions. Dobutamine hydrochloride should not be used in conjunction with other agents or diluents containing sodium bisulfite.

4.3 Contraindications

DBL Dobutamine Hydrochloride Injection is contraindicated in patients with idiopathic hypertrophic subaortic stenosis and previous hypersensitivity to dobutamine or any of the excipients.
Mechanical obstruction affecting left ventricular filling or outflow, especially in the case of obstructive cardiomyopathy or constrictive pericarditis.

4.4 Special Warnings and Precautions for Use

Increase in heart rate or blood pressure.

Dobutamine may cause a marked increase in heart rate or blood pressure, especially systolic pressure. Approximately 10 percent of patients in clinical studies have had rate increases of 30 beats/minute or more, and about 7.5 percent have had a 50 mmHg or greater increase in systolic pressure. Reduction of dosage usually reverses these effects promptly. Patients with pre-existing hypertension appear to face an increased risk of developing an exaggerated pressor response.

Increased atrioventricular conduction.

Dobutamine facilitates atrioventricular conduction, patients with atrial fibrillation are at risk of developing rapid ventricular response. In patients who have atrial fibrillation with rapid ventricular response, a digitalis preparation should be used prior to instituting therapy with dobutamine.

Ectopic activity.

Dobutamine may precipitate or exacerbate ventricular ectopic activity, but it rarely has caused ventricular tachycardia. It is recommended that precautions be taken in patients with a history of severe ventricular arrhythmia.

Impaired ventricular filling and ventricular outflow obstruction.

Inotropic agents, including dobutamine, do not improve haemodynamics in most patients with mechanical obstruction that hinders either ventricular filling or outflow, or both. Inotropic response may be inadequate in patients with markedly reduced ventricular compliance. Such conditions are present in cardiac tamponade, valvular aortic stenosis, and idiopathic hypertrophic subaortic stenosis. Minimal vasoconstriction has occasionally been observed, most notably in patients recently treated with a β-blocking drug.

Anaesthetics.

The myocardium may be sensitised to the effect of dobutamine by cyclopropane or halogenated hydrocarbon anaesthetics, and these should be avoided.

Hypersensitivity.

Reactions suggestive of hypersensitivity associated with the administration of dobutamine, including skin rash, fever, eosinophilia and bronchospasm, have been reported occasionally.
DBL Dobutamine Hydrochloride Injection solution contains sodium metabisulfite, which may cause allergic-type reactions, including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in susceptible people.

Usage for heart failure complicating an acute myocardial infarction.

Although the treatment of heart failure and the reduction in cardiac diameter will decrease myocardial oxygen consumption, there is still concern that the use of any positive inotropic agent may increase myocardial oxygen demand and the size of an infarction by intensifying ischaemia. Pertinent clinical data with dobutamine following acute myocardial infarction are limited but suggest that dobutamine does not have an adverse effect on the myocardium when used in doses that do not cause excessive increments in heart rate or arterial pressure. The dose of dobutamine should be titrated to prevent an excessive increase in heart rate and systolic blood pressure.
Animal studies have shown that massive doses of 30 mg/kg/min infused for 72 hours have produced irreversible myocardial damage.

General.

During the administration of dobutamine, as with any adrenergic agent, ECG and blood pressure should be continuously monitored. In addition, pulmonary wedge pressure and cardiac output should be monitored whenever possible to aid in the safe and effective infusion of dobutamine.
Hypovolaemia should be corrected with suitable volume expanders before treatment with dobutamine is instituted.
Because positive inotropic therapy can be associated with increases in intrapulmonary shunting, attention to arterial blood gases during treatment with dobutamine is recommended.
Dobutamine, like other beta-agonists, can produce a mild reduction in serum potassium concentration, rarely to hypokalemic levels. Accordingly, consideration should be given to monitoring serum potassium.
Precipitous decreases in blood pressure have occasionally been described in association with dobutamine therapy. Decreasing the dose or discontinuing the infusion typically results in rapid return of blood pressure to base-line values, but intervention may be required and reversibility may not be immediate.

Use in the elderly.

No data available.

Paediatric use.

The safety and efficacy of DBL Dobutamine Hydrochloride Injection for use in children have not been studied.

Effects on laboratory tests.

No abnormal laboratory values attributable to dobutamine have been observed.

4.5 Interactions with Other Medicines and Other Forms of Interactions

The potency of dobutamine may be decreased if the patient is given beta-adrenergic receptor antagonists. In such a case, the unopposed alpha-agonist effects of dobutamine may become apparent, including peripheral vasoconstriction and hypertension. Conversely, alpha-adrenergic blockade may make the beta1- and beta2-effects apparent, resulting in tachycardia and vasodilatation.
There was no evidence of interactions with other medicines in clinical studies in which dobutamine was administered concurrently with the following medicines: digitalis preparations, frusemide, spironolactone, lignocaine, isosorbide dinitrate, morphine, atropine, heparin, protamine, potassium chloride, folic acid and paracetamol.
Preliminary studies indicate that the concomitant use of dobutamine and nitroprusside results in a higher cardiac output and, usually, a lower pulmonary wedge pressure than when either medicine is used alone.
Studies on limited numbers of patients with heart failure demonstrate that the combination of dobutamine and glyceryl trinitrate results in a lower pulmonary wedge pressure than when dobutamine is used alone and a higher cardiac output than when glyceryl trinitrate is used alone.
Beta-blocker therapy, cyclopropane or halogenated hydrocarbon anaesthetics.
The effects of DBL Dobutamine Hydrochloride Injection may be enhanced by entacapone.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

No data available.
(Category B2)
Since there are no adequate and well-controlled studies in pregnant women, and since animal reproduction studies are not always predictive of human response, dobutamine hydrochloride should not be used during pregnancy unless the potential benefits outweigh the potential risks to the foetus.
 It is not known if dobutamine is distributed into breast milk. The decision of whether or not to treat lactating women with dobutamine should take into account the potential harmful effects to the infant. Should it be necessary to administer dobutamine to nursing mothers, breastfeeding should be suspended during the period of exposure.

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. Patients should refrain from driving or using machines until they know that the medicinal product does not negatively affect these abilities.

4.8 Adverse Effects (Undesirable Effects)

Many of the adverse effects of dobutamine are a quantitative extension of the pharmacological actions. The following adverse effects have been reported.

Increased heart rate, blood pressure, and ventricular ectopic activity.

A 10 to 20 mmHg increase in systolic blood pressure and an increase in heart rate of 5 to 15 beats per minute have been noted in most patients (see Section 4.4 Special Warnings and Precautions for Use regarding exaggerated chronotropic and pressure effects). Approximately 5 percent of patients have had increased premature ventricular beats during infusions. These effects are dose related and their occurrence may require that the dose be reduced.
Electrocardiogram ST segment elevation has also been observed.

Cardiac disorders.

Myocardial rupture, myocardial ischemia, eosinophilic myocarditis ventricular fibrillation ventricular tachycardia, angina pectoris, arteriospasm coronary, Stress cardiomyopathy, arrhythmia, ventricular dysfunction tachycardia, ventricular extrasystoles, palpitations.

Respiratory, thoracic and mediastinal disorders.

Dyspnea.

Hypotension.

Precipitous decreases in blood pressure have occasionally been described in association with dobutamine therapy. Decreasing the dose or discontinuing the infusion typically results in rapid return of blood pressure to baseline values. In rare cases, however, intervention may be required and reversibility may not be immediate.

Miscellaneous uncommon effects.

The following adverse effects have been reported in 1 to 3 percent of patients: nausea, headache, anginal pain, nonspecific chest pain, palpitations and shortness of breath.
Isolated cases of thrombocytopenia have been reported.
Administration of dobutamine, like other catecholamines, can produce a mild reduction in serum potassium concentration, rarely to hypokalaemic levels (see Section 4.4 Special Warnings and Precautions for Use).

Immune system disorders.

Hypersensitivity reactions including rash, pruritus of the scalp, fever, eosinophilia, anaphylactic shock and bronchospasm.

Reaction at site of intravenous infusion.

Phlebitis has occasionally been reported. Local inflammatory changes have been described following inadvertent infiltration. Isolated cases of cutaneous necrosis have been reported.

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

Overdoses of dobutamine have been reported rarely. The following is provided to serve as a guide if such an overdose is encountered.

Signs and symptoms.

Toxicity from dobutamine hydrochloride is usually due to excessive cardiac beta-receptor stimulation. The duration of action of dobutamine hydrochloride is generally short (T½ = 2 minutes) because it is rapidly metabolised by catechol-O-methyltransferase. The symptoms of toxicity may include anorexia, nausea, vomiting, tremor, anxiety, palpitations, headache, shortness of breath and anginal and nonspecific chest pain. The positive inotropic and chronotropic effects of dobutamine on the myocardium may cause hypertension, tachyarrhythmias, myocardial ischemia, and ventricular fibrillation. Hypotension may result from vasodilation.
If the product is ingested, unpredictable absorption may occur from the mouth and the gastrointestinal tract.

Treatment.

Because the duration of action of dobutamine is short, reducing the rate of administration or temporarily discontinuing dobutamine therapy until the patient's condition stabilises is usually adequate. However, in managing overdosage, consider the possibility of multiple drug overdoses, interaction among drugs, and unusual drug kinetics in the patient.
The initial actions to be taken in a dobutamine hydrochloride overdose are discontinuing administration, establishing an airway, and ensuring oxygenation and ventilation. Resuscitative measures should be initiated promptly. Severe ventricular tachyarrhythmias may be successfully treated with propranolol or lignocaine. Hypertension usually responds to a reduction in dose or discontinuation of therapy.
Protect the patient's airway and support ventilation and perfusion. If needed, meticulously monitor and maintain, within acceptable limits, the patient's vital signs, blood gases, serum electrolytes, etc. Absorption of drugs from the gastrointestinal tract may be decreased by giving activated charcoal, which, in many cases, is more effective than emesis or lavage. Repeated doses of charcoal over time may hasten elimination of some drugs that have been absorbed. Safeguard the patient's airway when employing gastric emptying or charcoal.
Forced diuresis, peritoneal dialysis, hemodialysis, or charcoal hemoperfusion have not been established as beneficial for an overdose of dobutamine hydrochloride.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Dobutamine hydrochloride is an inotropic agent whose primary activity results from stimulation of the beta-receptors of the heart while producing comparatively mild chronotropic, hypertensive, arrhythmogenic and vasodilative effects. The drug is believed to be a direct agonist which, in animal studies, produces less increase in heart rate and less decrease in peripheral vascular resistance for a given inotropic effect than does isoprenaline.
In patients with depressed cardiac function, both dobutamine and isoprenaline increase the cardiac output to a similar degree. In the case of dobutamine, this increase is usually not accompanied by marked increases in heart rate (although tachycardia is occasionally observed), and the cardiac stroke volume is usually increased. In contrast, isoprenaline increases the cardiac index primarily by increasing the heart rate while stroke volume changes little or declines.
Facilitation of atrioventricular conduction has been observed in human electrophysiologic studies in normal subjects and in patients with atrial fibrillation.
Systemic vascular resistance is usually decreased with administration of dobutamine. Occasionally, minimal vasoconstriction has been observed.
The onset of action is within one to two minutes; however, as much as ten minutes may be required to obtain the peak effect of a particular infusion rate.

Clinical trials.

Most clinical experience with dobutamine is short-term, up to several hours in duration. In the limited number of patients who were studied for 24, 48 and 72 hours, a persistent increase in cardiac output occurred in some, whereas the output of others returned toward base-line values. Infusions of up to 72 hours have revealed no adverse effects other than those seen with shorter infusions.

5.2 Pharmacokinetic Properties

Metabolism.

The plasma half-life of dobutamine in humans is two minutes. The major routes of metabolism are methylation of the catechol and conjugation.

Excretion.

In human urine the major excretion products are the conjugates of dobutamine and 3-O-methyl dobutamine. The 3-O-methyl derivative of dobutamine is inactive.

5.3 Preclinical Safety Data

Genotoxicity.

No data available.

Carcinogenicity.

No data available.

6 Pharmaceutical Particulars

6.1 List of Excipients

Sodium metabisulfite, water for injections.

6.2 Incompatibilities

Dobutamine is incompatible with alkaline solutions such as sodium bicarbonate 5%.
Do not add DBL Dobutamine Hydrochloride Injection to 5% sodium bicarbonate injection or any other strongly alkaline solutions. Dobutamine hydrochloride should not be used in conjunction with other agents or diluents containing sodium bisulfite.

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. Protect from light.

Compatibilities.

DBL Dobutamine Hydrochloride Injection when diluted to 250 microgram/mL and 500 microgram/mL with 0.9% sodium chloride injection and 5% glucose injection, was found to be stable for 24 hours at room temperature and in the presence of fluorescent light.

6.5 Nature and Contents of Container

DBL Dobutamine Hydrochloride Injection (250 mg/20 mL) is available in single vial.

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 structure.


Chemical name: (RS)-4-[2- [[3-(4-hydroxyphenyl)-1 -methylpropyl]amino]-ethyl] benzene-1,2-diol hydrochloride.
Molecular formula: C18H25NO3.HCl.
Molecular weight: 337.9.

CAS number.

49745-95-1.

7 Medicine Schedule (Poisons Standard)

S4 - Prescription Only Medicine.

Summary Table of Changes