Best Carisoprodol

Strains, sprains, and other muscle injuries can result in pain, stiffness, and muscle spasms. Muscle relaxants do not heal the injuries, but they do relaxmuscles and help ease discomfort and stop muscle spasms. The muscle relaxantcyclobenzaprine (Flexeril) is also sometimes used to treat fibromyalgia, a condition that involves aches, stiffness, and fatigue.

Muscle relaxants work by acting on the central nervous system. In the UnitedStates, they are available only with a physician’s prescription. Examples of muscle relaxants are carisoprodol (Soma), chlorzoxazone (Parafon Forte DSC),cyclobenzaprine (Flexeril), and methocarbamol (Robaxin). Most come only in tablet form. However, methocarbamol (Robaxin) is available in both tablet and injectable forms. Some muscle relaxants are available in Canada without a prescription.

Muscle relaxants are usually prescribed along with rest, exercise, physical therapy, or other treatments. Although the drugs may provide relief, they should never be considered a substitute for these other forms of treatment. Thesedrugs may make the injury feel so much better that one is tempted to go backto normal activity, but doing too much too soon can actually make the injuryworse.

Muscle relaxants work quite well for relieving muscle pain due to injuries, but are not effective for other types of pain. Some people feel drowsy, dizzy,confused, lightheaded, or less alert when using muscle relaxants drugs. These drugs may also cause blurred vision, clumsiness, or unsteadiness.

Carisoprodol is a centrally-acting skeletal muscle relaxant. It is a colorless, crystalline powder, having a mild characteristic odor and a bitter taste. Carisoprodol is slightly soluble in water and freely soluble in alcohol, chloroform and acetone. The drug’s solubility is practically independent of pH. Carisoprodol is marketed in the United States under the brand name Soma, and in the United Kingdom and other countries under the brand names Sanoma and Carisoma. The drug is available by itself or mixed with aspirin and in one preparation (Soma Compound With Codeine) along with codeine and caffeine as well.

SOMA (carisoprodol) Tablets are available as 250 mg and 350 mg round, white tablets. Carisoprodol is a white, crystalline powder, having a mild, characteristic odor and a bitter taste. It is slightly soluble in water; freely soluble in alcohol, in chloroform, and in acetone; and its solubility is practically independent of pH. Carisoprodol is present as a racemic mixture. Chemically, carisoprodol is N-isopropyl-2-methyl-2-propyl-1,3-propanediol dicarbamate and the molecular formula is C12H24N2O4, with a molecular weight of 260.33. The structural formula is:

SOMA is indicated for the relief of discomfort associated with acute, painful musculoskeletal conditions in adults.   SOMA should only be used for short periods (up to two or three weeks) because adequate evidence of effectiveness for more prolonged use has not been established and because acute, painful musculoskeletal conditions are generally of short duration.

Drug Dependence, Withdrawal, and Abuse

In the postmarketing experience with SOMA, cases of dependence, withdrawal, and abuse have been reported with prolonged use. Most cases of dependence, withdrawal, and abuse occurred in patients who have had a history of addiction or who used SOMA in combination with other drugs with abuse potential. However, there have been post-marketing adverse event reports of SOMA-associated abuse when used without other drugs with abuse potential. Withdrawal symptoms have been reported following abrupt cessation after prolonged use. To reduce the chance of SOMA dependence, withdrawal, or abuse, SOMA should be used with caution in addiction-prone patients and in patients taking other CNS depressants including alcohol, and SOMA should not be used more than two to three weeks for the relief of acute musculoskeletal discomfort.

SOMA, and one of its metabolites, meprobamate (a controlled substance), may cause dependence.

Seizures

There have been postmarketing reports of seizures in patients who received SOMA. Most of these cases have occurred in the setting of multiple drug overdoses (including drugs of abuse, illegal drugs, and alcohol).

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility

Long term studies in animals have not been performed to evaluate the carcinogenic potential of carisoprodol.

SOMA was not formally evaluated for genotoxicity. In published studies, carisoprodol was mutagenic in the in vitro mouse lymphoma cell assay in the absence of metabolizing enzymes, but was not mutagenic in the presence of metabolizing enzymes. Carisoprodol was clastogenic in the in vitro chromosomal aberration assay using Chinese hamster ovary cells with or without the presence of metabolizing enzymes. Other types of genotoxic tests resulted in negative findings. Carisoprodol was not mutagenic in the Ames reverse mutation assay using S. typhimurium strains with or without metabolizing enzymes, and was not clastogenic in an in vivo mouse micronucleus assay of circulating blood cells.

SOMA was not formally evaluated for effects on fertility. Published reproductive studies of carisoprodol in mice found no alteration in fertility although an alteration in reproductive cycles characterized by a greater time spent in estrus was observed at a carisoprodol dose of 1200 mg/kg/day. In a 13-week toxicology study that did not determine fertility, mouse testes weight and sperm motility were reduced at a dose of 1200 mg/kg/day. In both studies, the no effect level was 750 mg/kg/day, corresponding to approximately 2.6 times the human equivalent dosage of 350 mg four times a day, based on a body surface area comparison. The significance of these findings for human fertility is not known.

Use In Specific Population

Pregnancy: Pregnancy Category C.

There are no data on the use of SOMA during human pregnancy. Animal studies indicate that carisoprodol crosses the placenta and results in adverse effects on fetal growth and postnatal survival. The primary metabolite of carisoprodol, meprobamate, is an approved anxiolytic. Retrospective, post-marketing studies do not show a consistent association between maternal use of meprobamate and an increased risk for particular congenital malformations.

Teratogenic effects

Animal studies have not adequately evaluated the teratogenic effects of carisoprodol. There was no increase in the incidence of congenital malformations noted in reproductive studies in rats, rabbits, and mice treated with meprobamate. Retrospective, post-marketing studies of meprobamate during human pregnancy were equivocal for demonstrating an increased risk of congenital malformations following first trimester exposure. Across studies that indicated an increased risk, the types of malformations were inconsistent.

Nonteratogenic effects

In animal studies, carisoprodol reduced fetal weights, postnatal weight gain, and postnatal survival at maternal doses equivalent to 1-1.5 times the human dose (based on a body surface area comparison). Rats exposed to meprobamate in-utero showed behavioral alterations that persisted into adulthood. For children exposed to meprobamate in-utero, one study found no adverse effects on mental or motor development or IQ scores. SOMA should be used during pregnancy only if the potential benefit justifies the risk to the fetus.

Labor and Delivery

There is no information about the effects of SOMA on the mother and the fetus during labor and delivery.

Nursing Mothers

Very limited data in humans show that SOMA is present in breast milk and may reach concentrations two to four times the maternal plasma concentrations. In one case report, a breast fed infant received about 4-6% of the maternal daily dose through breast milk and experienced no adverse effects. However, milk production was inadequate and the baby was supplemented with formula. In lactation studies in mice, female pup survival and pup weight at weaning were decreased. This information suggests that maternal use of SOMA may lead to reduced or less effective infant feeding (due to sedation) and/or decreased milk production. Caution should be exercised when SOMA is administered to a nursing woman.

Pediatric Use

The efficacy, safety, and pharmacokinetics of SOMA in pediatric patients less than 16 years of age have not been established.

Geriatric Use

The efficacy, safety, and pharmacokinetics of SOMA in patients over 65 years old have not been established.

Renal Impairment

The safety and pharmacokinetics of SOMA in patients with renal impairment have not been evaluated. Since SOMA is excreted by the kidney, caution should be exercised if SOMA is administered to patients with impaired renal function. Carisoprodol is dialyzable by hemodialysis and peritoneal dialysis.

Hepatic Impairment

The safety and pharmacokinetics of SOMA in patients with hepatic impairment have not been evaluated. Since SOMA is metabolized in the liver, caution should be exercised if SOMA is administered to patients with impaired hepatic function.

Patients with Reduced CYP2C19 Activity

Patients with reduced CYP2C19 activity have higher exposure to carisoprodol. Therefore, caution should be exercised in administration of SOMA to these patients.

Carisoprodol Interactions with Medicines

Using carisoprodol with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Adinazolam
• Alfentanil
• Alprazolam
• Amobarbital
• Anileridine
• Aprobarbital
• Bromazepam
• Brotizolam
• Butabarbital
• Butalbital
• Carisoprodol
• Chloral Hydrate
• Chlordiazepoxide
• Chlorzoxazone
• Clobazam
• Clonazepam
• Clorazepate
• Codeine
• Dantrolene
• Diazepam
• Estazolam
• Ethchlorvynol
• Fentanyl
• Flunitrazepam
• Flurazepam
• Halazepam
• Hydrocodone
• Hydromorphone
• Ketazolam
• Levorphanol
• Lorazepam
• Lormetazepam
• Medazepam
• Meperidine
• Mephenesin
• Mephobarbital
• Meprobamate
• Metaxalone
• Methocarbamol
• Methohexital
• Midazolam
• Morphine
• Morphine Sulfate Liposome
• Nitrazepam
• Nordazepam
• Oxazepam
• Oxycodone
• Oxymorphone
• Pentobarbital
• Phenobarbital
• Prazepam
• Primidone
• Propoxyphene
• Quazepam
• Remifentanil
• Secobarbital
• Sodium Oxybate
• Sufentanil
• Temazepam
• Thiopental
• Triazolam

Carisoprodol Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Dosage Forms And Strengths

250 mg Tablets: round, convex, white tablets, inscribed with SOMA 250

350 mg Tablets: round, convex, white tablets, inscribed with SOMA 350

Storage and Handling

250 mg Tablets: round, convex, white tablets, inscribed with SOMA 250; available in bottles of 100 (NDC 0037-2250-10) and bottles of 30 (NDC 0037-2250-30).

350 mg Tablets: round, convex, white tablets, inscribed with SOMA 350; available in bottles of 100 (NDC 0037-2001-01).