Click here to view a Print Quality PDF of this table

Black Box Warning*  

Mechanism of Action

Blocks calcium - dependent contractions in cardiac and peripheral smooth muscle leading to vasodilation; slows cardiac conduction through the AV node


Acute setting: 0.25 mg/kg (average 20 mg) IV over 2 min; may give 2 nd bolus ( 0.35 mg/kg, average 25 mg) can be given 15 minutes later if HR > 100 bpm), then 5 to 15 IV mg/hr .

Continuous IV therapy should not be administered for longer than 24 hours

Non-acute setting or maintenance: 120 to 480 mg PO daily.

Can switch to slow-release drug, which is available and preferred.

Elderly: Initiate dosage at the lower end of the adult range

Hepatic Impairment: May accumulate; dose based on clinical response

Renal Impairment: No dosage adjustment needed

  • acute MI and pulmonary congestion
  • hypotension (SBP <90)
  • sick sinus syndrome without pacemaker
  • 2nd or 3rd degree AV block without pacemaker
  • Major Side Effects

    hypotension, heart block, HF

    Dosage forms and Strengths

    30 mg, 60 mg, 90 mg, 120 mg immediate - release tablets
    120 mg, 180 mg, 240 mg, 300 mg, 360 mg, 420 mg extended - release capsules 120 mg, 180 mg, 240 mg extended-release tablets

    100 mg powder for injection
    125 mg/25 mL, 50 mg/10 mL, 25 mg/5 mL, 5 mg/mL solution for injection

    Special Notes

    Many diltiazem products are not equivalent on a mg:mg basis ; monitor response and side effects when interchanging between products.

    Cardizem LA is a chronotherapeutic product; give at bedtime to blunt early morning surge in blood pressure


    Contents of extended-release capsules may be sprinkled over food, but do not chew or crush contents

    * Refer to prescribing information for more complete information.
    †Dosages given in the table may differ from those recommended by the manufacturers.


    1. American College of Cardiology (ACC), American Heart Association (AHA), and the European Society of Cardiology (ESC). ACC/AHA/ESC 2006 Guidelines for the Management of Patients with Atrial Fibrillation. Washington, DC: American College of Cardiology.
    2. Heart Rhythm Society. AF360 Pocket Guide: Practical Rate and Rhythm Management of Atrial Fibrillation. 2010, Washington, DC: Heart Rhythm Society.
    3. Tarascon Pocket Pharmacopoeia® 2012.