Diltiazem

pharmacological · cardiovascular · digestive · Oral · IV

Diltiazem. Non-dihydropyridine CCB — Cav1.2 blocker with both vascular and cardiac (AV-nodal) effects. Used for AF rate control + hypertension.… Oral half-life 11 h.

Non-dihydropyridine CCB — Cav1.2 blocker with both vascular and cardiac (AV-nodal) effects. Used for AF rate control + hypertension. Moderate CYP3A4 inhibitor → significant DDI footprint (statin myopathy, raised cyclosporine, raised carbamazepine).

PK: THREE OF FOUR VALUES VERIFY AND THE SHARED CITATION IS LEGITIMATE. My route-mismatch suspicion is refuted — the paper has a real intravenous arm: "10-minute intravenous infusion of a 20-mg dose; oral administration of 120 mg in solution form; and oral administration of 120 mg as two 60-mg sustained-release tablets". The half-life of 11.2 h is verbatim and intravenous; F 0.44 is verbatim and comes from the SOLUTION arm, matching what this row models rather than the sustained-release one; and V 777 L is 11.1 L/kg x 70 reported under "Following intravenous administration", so CLASS 6 IS ACQUITTED. ka 3.6 appears nowhere and is not a back-derivation either, implying a 1.15 h peak that matches neither the solution 38 minutes nor the tablets 165. Caveats recorded rather than acted on: 11.2 h and 11.1 L/kg are both two to three times the usual consensus, from an outlier 1984 assay; and these are SINGLE-DOSE values in a drug that inhibits its own metabolism. All three references are CYP3A4 victim studies with no diltiazem pharmacokinetics, and all three are correctly filed. INTERACTIONS: NO SINGLE ASSUMED CONCENTRATION FITS THIS BLOCK — its four edges imply 0.35, 0.27, 0.50 and an unresolved fourth, so unlike every other block audited it was not built from one constant. NOTHING IS RELABELLED HERE. Its sibling verapamil does invert through 0.5 µM on two of three edges, which makes the inconsistency specific to this record rather than to the pair.

Pharmacokinetics

Related compounds

Sources: PMID:9663178, PMID:8198928, PMID:9797793