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Diltiazem and verapamil
Pharmacokinetic properties
A table of the pharmacokinetic properties of diltiazem and verapamil is available for reference purposes.
These mainly stem from the blockade of L-type Ca2+ channels in smooth and cardiac muscle.
Use in the treatment of hypertension:
Compared with the dihydropyridines, these drugs are much less frequently used in the treatment of hypertension.
They are sometimes used alone as first line treatment of hypertension particularly in patients aged >55 years or patients of Afro-Caribbean origin.
Diltiazem is suitable for use in patients for whom antagonists at b-adrenoceptors are contra-indicated or are ineffective.
Verapamil is NOT used in combination with antagonists at b-adrenoceptors or given to patients recently treated with antagonists at b-adrenoceptors (risk of hypotension and asystole).
Diltiazem and verapamil are both likely to exacerbate heart failure or heart block and are contraindicated in patients with either of these conditions.
