Nicardipine
Nicardipine. Dihydropyridine CCB — vascular Cav1.2 selectivity. IV continuous infusion form for hypertensive emergencies + intraoperative HTN.… Oral half-life 4 h.
Dihydropyridine CCB — vascular Cav1.2 selectivity. IV continuous infusion form for hypertensive emergencies + intraoperative HTN. Less reflex tachycardia than IR nifedipine.
PK: F 0.3 was the EXACT MIDPOINT of a stated "15-45% approximately over the dose range 10-40 mg", and the same abstract says bioavailability "was found to be non-linearly related to dose" — so a scalar is wrong in kind, not merely imprecise. The stated LOWER endpoint is now stored and understates exposure at higher doses; the range belongs in any interpretation. V 600 L was about 8.6x the only human measurement: Guerret 1989 (PMID:2598970), six healthy men dosed intravenously with deuterium-labelled drug, verbatim "the volume of distribution was of the order of 1 l/kg and the half-life of beta-elimination ranged from 4 to 5 h" — 70 L at 70 kg, a true volume, and the stored 3 h appears in neither paper. That study also confirms disposition is THREE-compartment and route-independent. ka 1.5 /h dropped.
Pharmacokinetics
- Oral — t½ 4 h · F 15% · Vd 70 L
- IV — t½ 4 h · F 100% · Vd 70 L
Sources: PMID:6527979, PMID:9612662, PMID:2598970, PMID:2413297