Amrix (cyclobenzaprine) is a muscle relaxer used to alleviate pain, stiffness, and other discomfort from muscle injury. It also occasionally see off-label use in fibromyalgia and tetanus. The medication works on the central nervous system (CNS) to produce its muscle-relaxing effects.

This product is meant to supplement, not replace, rest, physical therapy, and other measures meant to aid with healing. It is often used to help with pain and stiffness from:

• Muscle strains
• Muscle sprains
• Sports injuries
• Other muscle injuries

The medication is typically not suitable for neurologic disorders, such as cerebral palsy.

Amrix can be used in children, but for those under age 16 dosage modification will likely be needed.

What to Expect from Amrix

Amrix is available in tablets, either 5 mg, 15 mg, or 30 mg. The medication is taken just once per day, with or without food according to personal preference.

Smaller, 5 mg doses are typically reserved for use in children, though some adults with relatively mild pain may find them sufficient as well. Treatment in patients age 16 and up is usually:

• Start with 15 mg taken once per day.
• If insufficient, dosage may be increased to 30 mg once per day.
• Treatment should not extend past three weeks of consecutive use.

Note that multiple smaller-dose tablets can be taken together for the same effect as a single larger dose. That is, taking three 5 mg tablets provides the same benefit as a single 15 mg tablet, or two 15 mg tablets provide the same benefit as a single 30 mg tablet.

If using capsules, they can be opened and the contents sprinkled onto soft, moist food, such as applesauce. They should not be chewed, however.

The reason treatment should not extend past three weeks is twofold:

• The conditions Amrix treats rarely extend past that time; and
• Effects of taking the medication longer are unknown.

It is very difficult to say what would happen if treatment continued long term; perhaps nothing at lower doses of 5 mg per day, but given that it does directly influence the CNS and life-threatening side effects are possible at higher, 30 mg doses, it's a dangerous gamble for little benefit.

Patients who take Amrix as directed find muscle pain is significantly improved, enabling greater range of motion and better compliance with physical therapy.

Side Effects & Interactions

Most patients will experience at least a few side effects from Amrix, though they're not necessarily negatives---the most common is drowsiness, affecting about 40% of patients. Since bed rest is advised in most muscle injuries anyway, this may be somewhat beneficial.

Other common side effects include:

• Dizziness
• Dry mouth
• Constipation
• Nausea
• Abdominal discomfort

Rarely more serious side effects develop. These are more common at higher doses, and more common among the elderly. Seek medical attention if experiencing:

• Fast, slow, or irregular heartbeat
• Agitation
• Hallucinations
• Fever
• Muscle twitching
• Loss of coordination
• Muscle stiffness

Alcohol should be avoided until its clear how Amrix affects an individual; those prone to drowsiness or dizziness may want to avoid it through the duration of treatment.

Monoamine oxidase inhibitors (MAOIs) should not be taken within 14 days before or after taking Amrix.

Other medications may interact with Amrix. Double-check with a doctor or pharmacist before mixing other treatments with Amrix.