📋 Indications & Clinical Dosage
*Hypertension:*
ORAL: Adult: Initially 100 mg daily, increased if necessary to 200 mg daily in 1-2 divided doses, high doses are rarely required; max. 400 mg per day
*Angina:*
ORAL: Adult: 50-100 mg 2-3 times a day
*Arrhythmias:*
Adult: Usual dose 50 mg 2-3 times a day, then increased if necessary up to 300 mg daily in divided doses.
BY IV INJ: Adult: Up to 5 mg, at a rate of1-2 mg/minute, then up to 5 mg after 5 minutes if required, total dose of 10-15 mg
*Migraine prophylaxis:*
ORAL: Adult: 100-200 mg daily in divided doses.
*Hyperthyroidism (adjunct):*
ORAL: Adult: 50 mg 4 times a day.
*During surgery:*
BY SLOW IV INJ: Adult: Initially 2-4 mg, given at induction or to control arrhythmias developing during anaesthesia, then 2 mg, repeated if necessary; max. 10 mg per course
*Early intervention within 12 hours of infarction:*
BY IV INJ: Adult: Initially 5 mg every 2 minutes, to a max. of 15 mg, followed by (oral) 50 mg every 6 hours for48 hours, to be taken 15 minutes after IV injection; (oral) maintenance 200 mg daily in divided doses.
Children: Not recommended.
💊 Mode of Administration
Administer IV Push: inject slowly over 1 min.
⛔ Contraindications
5th or 3rd degree AV block (without pacemaker, severe bradycardia, sick sinus syndrome, un-controlled heart failure, cardiogenic shock, severe peripheral arterial disease, hypotension, metabolic acidosis, untreated pheochromocytoma, severe asthma or COP
⚠️ Precautions & Warnings
4th degree AV block, heart failure (avoid if un-controlled), peripheral arterial circulatory disorders (avoid if severe), Prinzmetals angina, myasthenia gravis, ischaemic heart disease, withdraw gradually, history of bronchospasm, diabetes, hyperthyroidi????????Calibri???????MingLiU???????Vrinda
🔄 Drug Interactions
Ca+ + antagonists, antihypertensives including centrally acting agent (e.g. clonidine), antiarrhythmics, antipsychotics. TCADs, MAOIs, fluvoxamine, barbiturates, cardiac glycosides, sympathomimetics, cimetidine, hydralazine, rifampicin, insulin/oral hypoglycaemics, NSAIDs, ergot derivatives, erythromycin, anaesthetics, diuretics
⚠️ Adverse Reactions / Side Effects
Cardiovascular effects including bradycardia, postural hypotension, increased AV block, cardiac arrhythmias, Raynauds phenomenon, cold extremities, sexual dysfunction, GI upset, sleep and CNS disturbances, skin reactions, fatigue, paraesthesia, peripheral neuropathy, arthralgia, myopathy, altered blood sugar haematology and lipid levels. Withdraw if unexplained dry eyes or rash. Rare: Heart failure, dyspnea, bronchospasm
🤰 Pregnancy & Lactation Safety
Pregnancy Risk:
Avoid, risk cannot be ruled out.
Lactation / Breastfeeding:
Caution advised or effect undetermined.
🧪 Compatibility & Storage Stability
Compatibility: Stable in D5W, NS.
Stability & Storage: Do not store above 30C (86F). Protect from light.
📚 Official Regulatory & Clinical References
- Drug Regulatory Authority of Pakistan (DRAP): Drug Registration, S.R.O. Price Gazettes & National Essential Medicines List (NEML).
- World Health Organization (WHO): Collaborating Centre for Drug Statistics Methodology (ATC/DDD Index).
- Formulary Standards: British National Formulary (BNF) & Pakistan National Formulary (PNF) guidelines.