Key takeaways
Orphenadrine (Norflex) and cyclobenzaprine (Flexeril, Fexmid, Amrix) are both muscle relaxants used to relieve muscle pain and discomfort. They are similar in that they are both prescribed for short-term muscle conditions and are not controlled substances. However, they differ in several ways. Orphenadrine is available as an oral tablet and injection, while cyclobenzaprine is available as immediate-release (IR) tablets and extended-release (ER) capsules. Orphenadrine is typically taken twice a day, whereas cyclobenzaprine IR tablets are taken three times a day, and the ER capsules are taken once a day. Both medications are available as a lower-cost generic. Common side effects of orphenadrine include dry mouth, headache, and drowsiness, while cyclobenzaprine can cause drowsiness, dry mouth, and dizziness. Orphenadrine can increase heart rate or cause an irregular heartbeat and should be used with caution in people with heart problems, while cyclobenzaprine is not recommended for those with severe liver problems.
