Isoprenaline

Brand names Medihaler-iso, Saventrine

Used in the following combined preparations None

General Information

Isoprenaline is a sympathomimetic drug that dilates the bronchioles (small air passages in the lungs) and improves the transmission of electrical signals in the heart. Administered by aerosol inhaler, the drug is used as a bronchodilator to relieve bronchospasm associated with asthma, bronchitis, and emphysema. Rarely, it is given intravenously as an emergency treatment for serious heart disorders and for the relief of severe asthma. Because isoprenaline may increase the heart rate, it is not suitable for those with heart disorders such as angina. For the same reason, however, it is used in heart block as an interim treatment before an artificial pacemaker is implanted.

Excessive use of isoprenaline may cause symptoms such as insomnia, headaches, agitation, and, in extreme cases, dangerous heart rhythms.

Information for Users

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken

Tablets, injection, inhaler.

Frequency and timing of doses

Every 2-8 hours (tablets); as required up to a maximum of 8 doses in 24 hours (inhaler).

Adult dosage range

90-840mg daily (tablets);

1-3 puffs per dose (inhaler).

Onset of effect

2-5 minutes (inhaler).

Duration of action

Up to 6 hours.

Diet advice

None.
Storage

Keep in a closed container in a cool, dry place out of the reach of children. Protect from light. Do not puncture or burn inhalers.

Missed dose

Do not take the missed dose. Take the next dose as usual.

Stopping the drug

Do not stop the drug without consulting your doctor; symptoms may recur.

Overdose Action

Seek immediate medical advice in all cases. Take emergency action if dizziness, fainting, palpitations, or loss of consciousness occur.

See Drug poisoning emergency guide.

Possible Adverse Effects

Many of the adverse effects disappear during treatment as your body adjusts to the medicine. However, palpitations
are a sign of excessive stimulation of the heart, and chest pain always requires prompt medical attention.
Interactions

Tricyclic antidepressants
These drugs may interact with isoprenaline, causing adverse effects on heart rhythm.

QUICK REFERENCE

Drug group Bronchodilator
Overdose danger rating High
Dependence rating Low
Prescription needed Yes
Available as generic No

Special Precautions

Be sure to tell your doctor if:

You have heart problems.

You have high blood pressure.

You have an overactive thyroid gland.

You have diabetes.

You suffer from nervous problems.

You are taking other medications.

Pregnancy

Safety in pregnancy not established. Discuss with your doctor.

Breast-feeding

It is not known whether the drug passes into breast milk. Discuss with your doctor.

Infants and children

Reduced dose necessary. Not recommended for treating respiratory conditions.

Over 60

Adverse effects are more likely to occur. Dosage will be closely monitored.

Driving and hazardous work

Avoid such activities until you have learned how isoprenaline affects you because the drug can cause dizziness and nervousness.

Alcohol

No known problems.

Surgery and general anaesthetics

Inform your doctor or dentist that you are taking this drug if you need an anaesthetic.

Prolonged Use

The effect of isoprenaline may wear off with prolonged use. However, reduced benefit from the drug may also indicate a worsening of asthma and should be brought to your doctor’s attention.