Labrycor (Isoprenaline Hydrochloride)

Isoprenaline Hydrochloride acts on the cardiovascular and respiratory systems to correct slow heart rhythms and relieve bronchoconstriction.

• Symptomatic bradycardia: raises heart rate to restore adequate cardiac output.
• Heart block: improves atrioventricular conduction and stabilises rhythm.
• Asthma or COPD exacerbations: provides bronchodilation to ease breathing.
• Cardiac arrest adjunct: supports heart activity during resuscitation efforts.

• Isoprenaline Hydrochloride non‑selectively stimulates β‑adrenergic receptors, increasing intracellular cyclic AMP. Elevated cAMP enhances calcium influx in cardiac myocytes, producing positive chronotropic and inotropic effects, while also relaxing bronchial smooth muscle, resulting in bronchodilation.

Isoprenaline Hydrochloride may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Tachycardia: excessive increase in heart rate.
• Palpitations: sensation of rapid or irregular heartbeat.
• Tremor: fine muscle shaking, especially in the hands.
• Headache: mild to moderate pain in the head.
• Nausea: feeling of stomach upset.
• Hyperglycaemia: transient rise in blood glucose levels.

Serious or Rare Side Effects

• Arrhythmias: potentially life‑threatening irregular heart rhythms.
• Myocardial ischaemia: reduced blood flow to heart muscle.
• Severe hypotension: dangerous drop in blood pressure.
• Pulmonary oedema: fluid accumulation in the lungs.
• Allergic reactions: rash, itching, or anaphylaxis.
• Cardiac arrest: rare but possible if dosing is inappropriate.

When using Isoprenaline Hydrochloride, clinicians should consider patient‑specific factors and monitor for adverse events.

• Cardiac history: assess for ischemic disease or arrhythmias before initiation.
• Concomitant β‑blockers: may blunt therapeutic response; adjust therapy accordingly.
• Diabetes: monitor blood glucose as hyperglycaemia can occur.
• Thyroid disease: hyperthyroid patients may experience exaggerated tachycardia.
• Pregnancy and lactation: use only if potential benefit justifies potential risk; data are limited.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Isoprenaline Hydrochloride can interact with several drug classes, requiring careful management.

Major Interactions (Avoid)

• β‑blockers: antagonize the drug’s β‑adrenergic effects, reducing efficacy.
• MAO inhibitors: may potentiate hypertensive responses.
• Tricyclic antidepressants: increase risk of arrhythmias.

Moderate Interactions (Monitor Closely)

• Diuretics: may exacerbate electrolyte imbalances, affecting cardiac rhythm.
• Digoxin: combined use can increase risk of arrhythmias.
• Other sympathomimetics: additive tachycardia and hypertension may occur.