Cardizem (Diltiazem)

Question 1

Drug Classification

Answer 1

Ca2+ channel blocker

Question 2

Mechanism of Action

Answer 2

• SMC* Ca2+ channel blocker -> inhibits calcium entry and the subsequent interaction of actin and myosin in smooth muscle cells -> smooth muscle relaxation and dilation of blood vessels
• Cardiac* Ca2+ channel blocker -> negative inotropy, chronotropy, dromotropy

Question 3

Pharmacokinetics

Answer 3

Onset of action- 3 minutes
Peak Effects- 7 minutes
Duration of effect- 1-3 hours
Half Life- 2 hours

Question 4

Indications/Field Use

Answer 4

• Rapid ventricular rates >150 associated with a-fib, a-flutter
• PSVT refractory to adenosine

Question 5

Contraindications

Answer 5

• Hypotension
• Decompensated cardiogenic shock
• V-Tac
• WPW

Question 6

Side Effects/Adverse Reactions

Answer 6

N&V, dizziness, HA, bradycardia, heart block, hypotension

Question 7

Dose

Answer 7

Adult:
1st dose- 0.25mg/kg IV/IO over 2 minutes usual dose 15-20mg
2nd dose- 0.35mg/kg

    Maintainance dose- 5-15mg/hr

Not for Pedi

Question 8

Precautions

Answer 8

Must be discarded after one month without refrigeration

Question 9

Drug-drug interaction

Answer 9

Do not give to pts receiving IV beta blockers. It will increase risk of profound bradycardia