Cyclobenzaprine Hydrochloride
FDA Drug Information • Also known as: Amrix, Cyclobenzaprine Hydrochloride, Fexmid, Tonmya
- Brand Names
- Amrix, Cyclobenzaprine Hydrochloride, Fexmid, Tonmya
- Route
- ORAL
- Dosage Form
- TABLET, FILM COATED
- Product Type
- HUMAN PRESCRIPTION DRUG
Description
DESCRIPTION Cyclobenzaprine hydrochloride, USP 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. If aqueous solutions are made alkaline, the free base separates. Cyclobenzaprine HCl, USP is designated chemically as 3-( 5H- dibenzo[ a , d ]cyclohepten-5-ylidene)- N , N -dimethyl-1-propanamine hydrochloride, and has the following structural formula: Cyclobenzaprine hydrochloride, USP is supplied as a 5 mg or 10 mg tablet for oral administration. Cyclobenzaprine hydrochloride tablets USP, 5 mg and 10 mg, contain the following inactive ingredients: croscarmellose sodium, D&C Yellow #10 aluminum lake, FD&C Blue #2 aluminum lake, FD&C Yellow #6 aluminum lake, hypromellose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polyvinyl alcohol, silicon dioxide, talc and titanium dioxide. 1
What Is Cyclobenzaprine Hydrochloride Used For?
INDICATIONS AND USAGE Cyclobenzaprine hydrochloride tablets, USP are indicated as an adjunct to rest and physical therapy for relief of muscle spasm associated with acute, painful musculoskeletal conditions. Improvement is manifested by relief of muscle spasm and its associated signs and symptoms, namely, pain, tenderness, limitation of motion and restriction in activities of daily living. Cyclobenzaprine hydrochloride tablets, USP should be used only for short periods (up to two or three weeks) because adequate evidence of effectiveness for more prolonged use is not available and because muscle spasm associated with acute, painful musculoskeletal conditions is generally of short duration and specific therapy for longer periods is seldom warranted. Cyclobenzaprine hydrochloride tablets, USP have not been found effective in the treatment of spasticity associated with cerebral or spinal cord disease, or in children with cerebral palsy.
Dosage and Administration
DOSAGE AND ADMINISTRATION For most patients, the recommended dose of cyclobenzaprine hydrochloride tablets, USP is 5 mg three times a day. Based on individual patient response, the dose may be increased to 10 mg three times a day. Use of cyclobenzaprine hydrochloride tablets, USP for periods longer than two or three weeks is not recommended (see INDICATIONS AND USAGE ). Less frequent dosing should be considered for hepatically impaired or elderly patients (see PRECAUTIONS, Impaired Hepatic Function , and Use in the Elderly ) .
Side Effects (Adverse Reactions)
ADVERSE REACTIONS Incidence of most common adverse reactions in the 2 double-blind ‡ , placebo-controlled 5 mg studies (incidence of > 3% on cyclobenzaprine hydrochloride 5 mg): Cyclobenzaprine HCl 5 mg N=464 Cyclobenzaprine HCl 10 mg N=249 Placebo N=469 Drowsiness 29% 38% 10% Dry Mouth 21% 32% 7% Fatigue 6% 6% 3% Headache 5% 5% 8% Adverse reactions which were reported in 1% to 3% of the patients were: abdominal pain, acid regurgitation, constipation, diarrhea, dizziness, nausea, irritability, mental acuity decreased, nervousness, upper respiratory infection and pharyngitis. The following list of adverse reactions is based on the experience in 473 patients treated with cyclobenzaprine hydrochloride 10 mg in additional controlled clinical studies, 7607 patients in the post-marketing surveillance program, and reports received since the drug was marketed. The overall incidence of adverse reactions among patients in the surveillance program was less than the incidence in the controlled clinical studies. The adverse reactions reported most frequently with cyclobenzaprine hydrochloride were drowsiness, dry mouth and dizziness. The incidence of these common adverse reactions was lower in the surveillance program than in the controlled clinical studies: ‡ Note: Cyclobenzaprine hydrochloride 10 mg data are from one clinical trial. Cyclobenzaprine hydrochloride 5 mg and placebo data are from two studies. Clinical Studies With Cyclobenzaprine HCl 10 mg Surveillance Program With Cyclobenzaprine HCl 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 3% of the patients were: fatigue/tiredness, asthenia, nausea, constipation, dyspepsia, unpleasant taste, blurred vision, headache, nervousness and confusion. The following adverse reactions have been reported in post-marketing experience or with an incidence of less than 1% of patients in clinical trials with the 10 mg tablet: Body as a Whole: Syncope; malaise. Cardiovascular: Tachycardia; arrhythmia; vasodilatation; palpitation; hypotension. Digestive: Vomiting; anorexia; diarrhea; gastrointestinal pain; gastritis; thirst; flatulence; edema of the tongue; abnormal liver function and rare reports of hepatitis, jaundice and cholestasis. Hypersensitivity: Anaphylaxis; angioedema; pruritus; facial edema; urticaria; rash. Musculoskeletal: Local weakness. Nervous System and Psychiatric: Seizures, ataxia; vertigo; dysarthria; tremors; hypertonia; convulsions; muscle twitching; disorientation; insomnia; depressed mood; abnormal sensations; anxiety; agitation; psychosis, abnormal thinking and dreaming; hallucinations; excitement; paresthesia; diplopia, serotonin syndrome. Skin: Sweating. Special Senses: Ageusia; tinnitus. Urogenital: Urinary frequency and/or retention. Causal Relationship Unknown Other reactions, reported rarely for cyclobenzaprine hydrochloride under circumstances where a causal relationship could not be established or reported for other tricyclic drugs, are listed to serve as alerting information to physicians: Body as a whole: Chest pain; edema. Cardiovascular: Hypertension; myocardial infarction; heart block; stroke. Digestive: Paralytic ileus, tongue discoloration; stomatitis; parotid swelling. Endocrine: Inappropriate ADH syndrome. Hematic and Lymphatic: Purpura; bone marrow depression; leukopenia; eosinophilia; thrombocytopenia. Metabolic, Nutritional and Immune: Elevation and lowering of blood sugar levels; weight gain or loss. Musculoskeletal: Myalgia. Nervous System and Psychiatric: Decreased or increased libido; abnormal gait; delusions; aggressive behavior; paranoia; peripheral neuropathy; Bell's palsy; alteration in EEG patterns; extrapyramidal symptoms. Respiratory: Dyspnea. Skin: Photosensitization; alopecia. Urogenital: Impaired urination; dilatation of urinary...
Warnings and Precautions
WARNINGS Serotonin Syndrome The development of a potentially life-threatening serotonin syndrome has been reported with Cyclobenzaprine Hydrochloride when used in combination with other drugs, such as selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), tramadol, bupropion, meperidine, verapamil, or (MAO) inhibitors. The concomitant use of Cyclobenzaprine Hydrochloride with MAO inhibitors is contraindicated (see CONTRAINDICATIONS ). Serotonin syndrome symptoms may include mental status changes (e.g., confusion, agitation, hallucinations), autonomic instability (e.g., diaphoresis, tachycardia, labile blood pressure, hyperthermia), neuromuscular abnormalities (e.g., tremor, ataxia, hyperreflexia, clonus, muscle rigidity) and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). Treatment with Cyclobenzaprine Hydrochloride and any concomitant serotonergic agents should be discontinued immediately if the above reactions occur and supportive symptomatic treatment should be initiated. If concomitant treatment with Cyclobenzaprine Hydrochloride and other serotonergic drugs is clinically warranted, careful observation is advised, particularly during treatment initiation or dose increases (see PRECAUTIONS, Drug Interactions ). Cyclobenzaprine is closely related to the tricyclic antidepressants, e.g., amitriptyline and imipramine. In short term studies for indications other than muscle spasm associated with acute musculoskeletal conditions, and usually at doses somewhat greater than those recommended for skeletal muscle spasm, some of the more serious central nervous system reactions noted with the tricyclic antidepressants have occurred (see WARNINGS , below, and ADVERSE REACTIONS ). Tricyclic antidepressants have been reported to produce arrhythmias, sinus tachycardia, prolongation of the conduction time leading to myocardial infarction and stroke. Cyclobenzaprine hydrochloride may enhance the effects of alcohol, barbiturates and other CNS depressants.
Contraindications
CONTRAINDICATIONS Hypersensitivity to any component of this product. Concomitant use of monoamine oxidase (MAO) inhibitors or within 14 days after their discontinuation. Hyperpyretic crisis seizures and deaths have occurred in patients receiving cyclobenzaprine (or structurally similar tricyclic antidepressants) concomitantly with MAO inhibitor drugs. Acute recovery phase of myocardial infarction, and patients with arrhythmias, heart block or conduction disturbances, or congestive heart failure. Hyperthyroidism.
Overdosage
OVERDOSAGE Although rare, deaths may occur from overdosage with cyclobenzaprine hydrochloride. Multiple drug ingestion (including alcohol) is common in deliberate cyclobenzaprine overdose. As management of overdose is complex and changing, it is recommended that the physician contact a poison control center for current information on treatment. Signs and symptoms of toxicity may develop rapidly after cyclobenzaprine overdose; therefore, hospital monitoring is required as soon as possible. The acute oral LD 50 of cyclobenzaprine hydrochloride is approximately 338 and 425 mg/kg in mice and rats, respectively. Manifestations The most common effects associated with cyclobenzaprine overdose are drowsiness and tachycardia. Less frequent manifestations include tremor, agitation, coma, ataxia, hypertension, slurred speech, confusion, dizziness, nausea, vomiting and hallucinations. Rare but potentially critical manifestations of overdose are cardiac arrest, chest pain, cardiac dysrhythmias, severe hypotension, seizures and neuroleptic malignant syndrome. Changes in the electrocardiogram, particularly in QRS axis or width, are clinically significant indicators of cyclobenzaprine toxicity. Other potential effects of overdosage include any of the symptoms listed under ADVERSE REACTIONS . Management General As management of overdose is complex and changing, it is recommended that the physician contact a poison control center for current information on treatment. In order to protect against the rare but potentially critical manifestations described above, obtain an ECG and immediately initiate cardiac monitoring. Protect the patient's airway, establish an intravenous line and initiate gastric decontamination. Observation with cardiac monitoring and observation for signs of CNS or respiratory depression, hypotension, cardiac dysrhythmias and/or conduction blocks, and seizures is necessary. If signs of toxicity occur at any time during this period, extended monitoring is required....
How Supplied
HOW SUPPLIED Cyclobenzaprine hydrochloride tablets, USP 5 mg are supplied as butterscotch yellow-colored, capsule-shaped, film-coated convex tablets, debossed with "AN40" on one side and plain on the other side. They are available as follows: 100 count bottle NDC 65162-540-10 500 count bottle NDC 65162-540-50 1000 count bottle NDC 65162-540-11 Cyclobenzaprine hydrochloride tablets, USP 10 mg are supplied as butterscotch yellow, round, film-coated convex tablets, debossed with "AN41" on one side and plain on the other side. They are available as follows: 100 count bottle NDC 65162-541-10 500 count bottle NDC 65162-541-50 1000 count bottle NDC 65162-541-11 Storage and Handling Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. This is a bulk package. Dispense contents with a child-resistant closure (as required) and in a tight, light-resistant container as defined in the USP. KEEP THIS AND ALL MEDICATION OUT OF THE REACH OF CHILDREN. Rx Only For more information, call 1-877-835-5472 or visit www.amneal.com. Distributed by Amneal Pharmaceuticals Bridgewater, NJ 08807 Rev. 10-2015-00
About This Information
This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.
What are side effects?
Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.
What are drug interactions?
Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.