Verapamil

Related Subjects: | Wolff-Parkinson White syndrome (WPW) AVRT | Lown Ganong Levine Syndrome AVRT | Supraventricular Tachycardia (SVT) | Atrioventricular Nodal Reentrant Tachycardia AVNRT | Atrial Flutter | Atrial Fibrillation | Sinus Tachycardia | Sinus Arrhythmia | Multifocal Atrial Tachycardia | Resuscitation - Adult Tachycardia Algorithm

Contraindicated in wide complex tachycardia where Ventricular tachycardia cannot be excluded. It is negatively chronotropic and inotropic

About : Always check the BNF link here

• Dihydropyridine Calcium channel blocker - inhibits slow inward Calcium current

Activity

• Binds to L type Calcium channels preventing Calcium influx
• Relaxes vascular smooth muscle and reduces peripheral resistance
• Slows AV nodal conduction and prolongs refractory period
• Negative inotrope and chronotropic

Indications, Dose and uses

• Acute use in SVT: Adenosine now first-line though Verapamil may be coming back into favour. If adenosine fails then consider Verapamil 2.5-5 mg IV over 5-10 min (max 10 mg) (avoid in suspected VT or with beta-blockers or WPW with AF).
• Angina: Verapamil 40mg TDS converted to the once-daily preparation (Verapamil SR at 120mg ). It can be titrated up to a maximum dose of 480 mg/d.
• Hypertension, Rate control in AF and atrial flutter, Migraine, Cluster headaches: dose as above

Dose range:You must check with BNF or drug datasheet

Interactions

• Severe Cautions with IV Beta-blockers causing heart block/asystole
• Verapamil and Amiodarone increases the risk of AV block
• Verapamil increases Digoxin levels

Contraindications

• Suspected Ventricular tachycardia, 2nd/3rd degree Heart block
• Severe Heart failure Hypotension, Acute porphyria

Side effects

• Constipation, headache, ankle swelling, Gingival hyperplasia
• Heart block, Chronic constipation, low BP, ankle oedema.

References

• Verapamil at BNF