Cyclobenzaprine: learn about side effects, dosage, special precautions, and more on MedlinePlus Find patient medical information for Flexeril oral on WebMD including its uses, side effects and safety, interactions, pictures, warnings and user ratings. Cyclobenzaprine, sold under the brand name Flexeril among others, is a medication used for muscle spasms from musculoskeletal conditions of sudden onset. It is not useful in cerebral palsy. It is taken by mouth. Use is not recommended for more than a few weeks. Common side effects include headache, feeling tired, dizziness, and dry mouth. FLEXERIL should be initiated with a 5 mg dose and titrated slowly upward. Drug Interactions FLEXERIL may have life-threatening interactions with MAO inhibitors. (See CONTRAINDICATIONS.) FLEXERIL may enhance the effects of alcohol, barbiturates, and other CNS depressants. Tricyclic antidepressants may block the antihypertensive action of guanethidine and similarly acting compounds. Tricyclic. Flexeril Description. Cyclobenzaprine hydrochloride is a white, crystalline tricyclic amine salt with the empirical formula C 20 H 21 N•HCl and a molecular weight of 311.9. It has a melting point of 217˚C, and a pK a of 8.47 at 25˚C. It is freely soluble in water and alcohol, sparingly soluble in isopropanol, and insoluble in hydrocarbon solvents. What is Flexeril? Flexeril (cyclobenzaprine) is a muscle relaxant.It works by blocking nerve impulses (or pain sensations) that are sent to your brain. Flexeril is used together with rest and physical therapy to treat skeletal muscle conditions such as pain, injury, or spasms. Flexeril may also be used for purposes not listed in this medication guide. Flexeril is an effective pharmacological treatment for muscle spasms and pain, but it can lead to an increased risk of side effects and dependency when mixed with alcohol. If you or a loved one has been prescribed Flexeril but are no longer using it as prescribed or you’re combining it with alcohol, it may be time to seek help. A number of treatment approaches are available to help treat. FLEXERIL 5 mg and placebo data are from two studies. Clinical Studies With FLEXERIL 10 mg: Surveillance Program With FLEXERIL 10 mg: Drowsiness: 39%: 16%: Dry Mouth: 27%: 7%: Dizziness: 11%: 3%: Among the less frequent adverse reactions, there was no appreciable difference in incidence in controlled clinical studies or in the surveillance program. Adverse reactions which were reported in 1% to. About GoodRx Prices and Flexeril Coupons GoodRx‘s cash prices are based on multiple sources, including published price lists, purchases, claims records, and data provided by pharmacies. Most of our discount and coupon prices are based on contracts between a pharmacy (or pharmacy purchasing group) and a Pharmacy Benefit Manager (PBM), who provides prices to us. COMMON BRAND NAME(S): Flexeril. USES: Cyclobenzaprine is used short-term to treat muscle spasms. It is usually used along with rest and physical therapy. It works by helping to relax the muscles. HOW TO USE: Take this medication by mouth with or without food as directed by your doctor. Do not increase your dose or use this drug more often or.