A "muscle relaxant" is any one of several prescription drugs used to treat back pain associated with muscle spasms. They are also prescribed for cerebral palsy, multiple sclerosis, and other conditions that cause involuntary spasms. Muscle relaxants do not actually relax muscles. Instead, they act on the brain and central nervous system to relax muscles, based on the theory that pain causes muscle spasms, which in turn causes pain. Two commonly prescribed muscle relaxants, carisoprodol and diazepam, routinely make the list of the top 20 most widely abused drugs in the United States.
Carisoprodol is prescribed for short-term back and muscle pain under the trademarked names of Vandom, Soma, Soma Compound with Aspirin, and Soma Compound with Codeine and Aspirin. It is metabolized in the liver and excreted through the kidneys, and therefore not recommended for people with kidney or liver diseases. It should not be used by people who have histories of alcoholism or substance abuse.
Side effects can be drowsiness, dizziness, confusion, headache, spinning sensation, shakiness, unsteady walk, nausea, irritability, and sleep problems. The effect of drowsiness is increased if carisoprodol is taken with sedatives, certain cold medicines, opiate painkillers, certain herbal remedies, alcohol, and any drug that causes sleepiness.
Since carisoprodol is not considered addictive, the government does not regulate it in the same way it keeps track of more dangerous drugs like heroin and oxycodone. This means that carisoprodol is available without a prescription in Mexico, and through veterinary services and Internet pharmacies.
The problem is that carisoprodol metabolizes into meprobamate, which is a highly addictive drug. Thousands of people go to emergency rooms every year for carisoprodol overdoses, and many more are addicted to it. For this reason, some people think that carisoprodol should be reclassified as a Schedule IV drug in the same way meprobamate is. Most fateful overdoses involve carisoprodol in combination with alcohol, codeine, meprobamate, or propoxyphene.
People who become addicted to carisoprodol have to undergo a withdrawal syndrome that has symptoms similar to withdrawal from meprobamate, pentobarbital, and chlordizapoxide. Symptoms are nervousness, anxiety, irritability, headaches, muscle pain, mental confusion, seizures, insomnia, and cramps. A person in severe withdrawal should be medically supervised.
Valium, another muscle relaxant, is one of the most popular drugs in the benzodiazepine family, and classified as a Schedule IV Controlled Substance, meaning it is somewhat addictive. It is most often prescribed for anxiety. Other benzodiazepines sometimes used as muscle relaxants are oxazepam, temazepam, lorazepam, bromazepam, prazepam, and brotizolam. These drugs interact with one another as well as many other drugs, including barbiturates, opiate painkillers, certain herbal remedies, alcohol, other muscle relaxants, narcotics, tranquilizers, and some dental anesthetics. Common side effects are shakiness, unsteady walk, trembling or other problems with muscle control, and drowsiness. Less common side effects can be constipation, decreased interest in sex, diarrhea, double vision, spinning sensation, restlessness, irritability, and mental problems. In some countries, these drugs can only be prescribed for one month or less. Benzodiazepines are not mild drugs, and have been associated with heart failure and paralysis in some patients.
People can become physically dependent on benzodiazepines, and when they stop using them, they will go through an unpleasant withdrawal syndrome that addicts often believe is worse than the one associated with heroin. Symptoms can be anxiety, tremors, nightmares, insomnia, vomiting, nausea, low blood pressure, seizures, delirium, fever, and hallucinations. Withdrawal is best done under medical supervision. Cyclobenzaprine is the third most common muscle relaxant. It is commonly sold under the brand names Amrix, Fexmid, Flexeril, and Tabradol, and used to treat sprains, strains, or any injury to the muscles. It is not prescribed to people with a history of glaucoma, urination problems, heart or blood vessel diseases, liver disease, or overactive thyroids. The most common side effect is drowsiness, and if you take it with other medications that cause drowsiness such as antihistamines, sedatives, tranquilizers, prescription pain killers, barbiturates, seizure medication, other muscle relaxants, or sleeping pills, this side effect will be strengthened. Other side effects can be irregular breathing, hives, puffiness or swelling of the eyelids, flushing, hallucinations, muscle stiffness, and convulsions.