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Drug Safety-related Labeling Changes (SrLC)

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TIAZAC (NDA-020401)

(DILTIAZEM HYDROCHLORIDE)

Safety-related Labeling Changes Approved by FDA Center for Drug Evaluation and Research (CDER)

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04/16/2025 (SUPPL-44)

Approved Drug Label (PDF)

7 Drug Interactions

Additions and/or revisions underlined:

Due to the potential for additive effects, caution and careful titration are warranted in patients receiving diltiazem hydrochloride concomitantly with other agents known to affect cardiac contractility and/orconduction (see WARNINGS). Pharmacologic studies indicate that there may be additive effects in prolonging AV conduction when using beta-blockers or digitalis concomitantly with Tiazac (see WARNINGS).

Diltiazem is both a substrate and an inhibitor of the Pg-p and cytochrome P450 3A4 enzyme system which may affect exposure to diltiazem and concomitant drugs metabolized by those pathways. Patients with renal and/or hepatic impairment may be particularly at risk of exposure changes.

11/18/2016 (SUPPL-42)

Approved Drug Label (PDF)

6 Adverse Reactions

(Addition underlined; Summary in italics)

 

Footnote addition to the following table:

MOST COMMON ADVERSE EVENTS IN DOUBLE-BLIND PLACEBO-CONTROLLED HYPERTENSION TRIALS*

 *Adverse events occurring in treated patients at 2% or more than placebo-treated patients.

7 Drug Interactions

(Addition underlined)


Ivabradine: Concurrent use of diltiazem increases exposure to ivabradine and may exacerbate bradycardia and conduction disturbances. Avoid concomitant use of ivabradine and diltiazem.

Statins: Diltiazem is an inhibitor of CYP3A4 and has been shown to increase significantly the AUC of some statins. The risk of myopathy and rhabdomyolysis with statins metabolized by CYP3A4 is increased with concomitant use of diltiazem. When possible, use a non-CYP3A4- metabolized statin with diltiazem. Otherwise, reduce the dose for both diltiazem and the statin and monitor for signs and symptoms of muscle toxicity.