Cyclobenazprine Hydrochloride (Muscle Relaxant)

Question 1

What are the brand names for cyclobenzaprine hydrochloride?

Answer 1

Amrix, Flexeril, Fexmid

Question 2

What dose tablets of Flexeril are available?

Answer 2

5 mg, 10 mg

Question 3

What does tablets of Fexmid are available?

Answer 3

7.5 mg

Question 4

What does extended release capsules are available for Amrix?

Answer 4

15 mg, 30 mg

Question 5

What is the FDA approved indication and dosage for cyclobenzaprine hydrochloride

Answer 5

Release of skeletal muscle spasm associated with acute, painful musculoskeletal conditions:

The recommended dose is 15 mg per day as 5 mg three times a day or one 15 mg extended release capsule once per day. Based on individual patient response, the dose may be increased to 30 mg per day and 130 mg extended release status or 10 mg three times a day. Do not use for periods longer than three weeks. Do not use more than 60 mg per day.

Not recommended for children under 15 years of age.

Question 6

What is the mechanism of action for cyclobenzaprine?

Answer 6

Cyclobenzaprine does not act directly on skeletal muscle or at the neuromuscular synapses. It probably exerts it’s effect by acting at the brainstem in the CNS. The overall effect is a reduction of tonic somatic motor activity influencing both alpha and gamma motoneurons.

Question 7

What are the drug interactions of Flexeril?

Answer 7

May enhance effects of alcohol and other CNS depressants. May decrease the effects of guanethidine.

Question 8

What are the contraindications for cyclobenzaprine?

Answer 8

• Contraindicated in patients with congestive heart failure, hypothyroidism, cardiac arrhythmia, conductive disturbances, and during acute recovery phase of myocardial infarction. Use with caution in patients with a history of urinary retention, closed angle glaucoma and increased intra-ocular pressure, and also during pregnancy and lactation.
• Pregnancy Category B

Question 9

What are the adverse effects of cyclobenzaprine hydrochloride?

Answer 9

Drowsiness, dizziness, dry mouth, fatigue, asthenia, nausea, constipation, dyspepsia, unpleasant taste, blurred vision, headache, nervousness, and confusion.

Question 10

What should the RPh tell the patient when counseling them for cyclobenzaprine hydrochloride?

Answer 10

• May cause drowsiness. Use caution while operating machinery or a mental alertness is required.
• Avoid alcohol while taking this medication.
• May cause dry mouth.
• If a dose is missed, skip it and return to the normal dosing schedule.