- Angina:
- PO 80-120mg TDS
- Max: 480mg/day
- Less than 120mg TDS is not likely to be effective in variant angina.
- Hypertension:
- SR: PO 180mg OD
- May be increased to either 180mg BD or 240mg AM and 120mg PM OR
- SR: PO 180mg OD
-
- PO 120mg OD
- If inadequate response, may increase dose at weekly intervals by: 180mg OD; 240mg OD; 360mg OD; 480mg OD
- Max; 480mg
- PO 120mg OD
- Paroxysmal supraventricular tachycardia (PSVT) conversion:
- IV 2.5-5mg *1 (over 2min), then 5-10mg every 15-30min PRN
- Max 20mg/dose OR
- IV 2.5-5mg *1 (over 2min), then 5-10mg every 15-30min PRN
-
- IV 5mg every 15min up to 30mg/total dose
- IV 5mg every 15min up to 30mg/total dose
- Prevention of paroxysmal supraventricular tachycardia (PSVT):
- PO 80mg-120mg TDS/QID
- Max 480mg/day
- Atrial fibrillation/flutter:
- IV 2.5-10mg *1
- May repeat 5-10mg dose after 15-30min
- For temporary control of rapid ventricular rate
- IV 2.5-10mg *1
-
- PO 80mg-120mg TDS/QID
- Max 480mg/day
- For control of ventricular rate in chronic disease
- PO 80mg-120mg TDS/QID
- Prophylaxis of cluster headaches (Off-label):
- PO 80mg TDS
- Dose adjusted based on the response
- Tablet:
- 40mg
- SR: 240mg
- Should be taken with food with oral route
- IV should be administered over 2 min (3 minutes in older patients)
Nondihydropyridine calcium-channel blocker
It inhibits transmembrane influx of extracellular calcium ions across membranes of myocardial cells and vascular smooth muscle cells without changing serum calcium concentrations, resulting in inhibition of cardiac and vascular smooth muscle contraction and thereby dilating main coronary and systemic arteries.
- Constipation
- Dizziness
- Nausea
- Hypotension
- Headache
- Edema
- CHF
- Fatigue
- Porphyria
- Hypotension (systolic pressure less than 90mmHg)
- Cardiogenic shock
- Bradycardia (pulse rate at rest less than 50 beats/min) except in patients with a functioning pacemaker.
- Second or third degree AV block with no pacemaker
- Sick sinus syndrome, including sino-atrial block
- Uncompensated heart failure
- Isocarboxazid
- Dantrolene
- Fezolinetant
- Flibanserin
- Lomitapide
- Lonafarnib
- Pimozide
Drug Status
| Availability | Prescription only |
| Pregnancy | Category C; Contraindicated |
| Breastfeeding | Not recommended |
| Schedule | Not controlled |
| BRAND NAME | STRENGTH | FORMULATION | PACK SIZE | MANUFACTURER | DISTRIBUTOR |
|---|---|---|---|---|---|
| Isoptin | 40mg | Tablet | 100’s | Abbott Labs | Harley’s Ltd |
| Isoptin SR | 240mg | Tablet | 30’s | Abbott Labs | Harley’s Ltd |
| Vera-Denk Retard | 240 mg | Tablet | 50’s | Denk Pharma | Laborex Kenya |