Muscle relaxants are used to treat conditions where muscles spasms and spasticity are a problem. Muscle spasms are caused by an involuntary contraction of the muscles, which is often painful and causes difficulty completing everyday tasks. Spasticity occurs when a muscle contracts and remains in this tight position, becoming very stiff andalmost impossible to use.
In cases like this, muscle relaxers are used to control stiffness and involuntary movements. A variety of conditions in the nervous system can cause these symptoms including multiple sclerosis, motor neuron disease, cerebral palsy or severe head and back injuries.
Commonly Used Muscle Relaxants
Your doctor has several options when prescribing muscle relaxers. Many of these drugs are very common, and your doctor will be able to work with you to find the medication that works best.
1. Baclofen (Lioresal, Baclosan)
Commonly prescribed for specificity from spinal cord injuries and multiple sclerosis, the central acting drug, baclofen, is a muscle relaxant that reduces the severity of muscle spasms and the frequency in which they occur. This reduction in muscle spasms works to relieve the pain, clonus, and muscle rigidity caused by spasticity. It has also been used off label to help treat alcoholism by easing withdrawal and encouraging abstinence.
How to take it: Sold under the brand names Liroesal and Remular, Baclofen is also available in several generic forms. Usually prescribed in tablet form, the average dose is 10 to 20 mg and is taken three to four times a day. If an injection is necessary, a dose of 0,5 mg/mL is administered. In medications like this, the dose is gradually increased and tapered.
Possible side effect: Common side effects include nausea, drowsiness, confusion, dizziness and fatigue. Less common side effects that you might notice are impaired eyesight, weakness, light headedness, headache, dry mouth, trouble breathing, aching muscles, sleeplessness, nightmares, sudden mood changes, poor balance, increase in passing of urine, shakiness, increased sweating and skin rash.
2. Carisoprodol (Soma, Carisona, Sodol)
Used for more than 50 years, carisoprodal is a central acting muscle relaxant that has not been seen to cause any hepatic injury. It is recommended to treat the acute pain that accompanies painful musculoskeletal disorders.
How to take it: Available in generic forms, and under the brand names of Soma, Carisoma and Vanadom, it is generally prescribed in tablet form at a dosage of 250 or 350 mg taken three or four times daily for a period of two to three weeks. Combinations that contain aspirin and codeine are not uncommon. Classified as a schedule IV drug that has an unlikely potential for dependence and abuse by patients, carisoprodol is available by prescription only.
Possible side effects: Dizziness, neuromuscular rigidity, myoclonus and seizures.
3. Chloraoxazone (Parafon, Forte, Remular)
A central acting drug, chlorzoxazone is an effective treatment for muscles spasms, although it is unclear if this is due to its sedative qualities or other mechanisms that are not known. Recommended for the treatment of low back pain and general muscle spasms, the effects are only considered to be fair. Despite the doubts of chloraosazone’s effectiveness, it is still widely used.
How to take it: Available in many generic forms, chloraoxazone is also available under the trade names Parafon, Forte and Remular. Recommended dose is tablets ranging from 250-750 mg, to be taken three to four times a day for a period of one to four weeks.
Possible side effects: Dizziness, drowsiness, headache, fever and tremor.
4. Cyclobenzaprine (Flexeril)
A tricyclic anti-depressant derivative, cyclobenzaprine uses a mechanism that is not yet known. The efficiency may have something to do with the sedative quality of the drug, as it is a central nervous system depressant, and is effective in treating acute muscle spasms caused by severe muscle disorders.
How to take it: Recommended dosage for adults is a 5 or 10 mg tablet to be taken three times daily for a period of three to four weeks. Available in generic form or under the brand names Flexeril, Flexamid and Amrix. 15 and 30 mg extended release capsules are also available.
Possible side effects: Sleepiness, dry mouth, dizziness and headache.
5. Dantrolene (Dantrium)
A lipid soluble diphenylhydantion analogue, dantrolene decreases muscle contractions by limiting the release of calcium. Used for the treatment of chronic spasticity, it is also useful in treating malignant hyperthermia due to its ability to block the release of calcium.
How to take it: Available in several generic forms and under the trade name Dantrium, it is prescribed in capsules of 25, 50 or 100mg. This drug needs to be gradually increased, and patients will start with a dosage of 25 mg with increases as advised by your doctor.
In the case of malignant hyperthermia, the initial dose 1mg/kg is delivered intravenously. In the case of prophylaxis against hypothermia, the delivery method is an oral dose of 4 to 8 mg/kg daily.
Possible side effects: Weakness, nausea, drowsiness, fatigue and dizziness.
6. Metaxalone (Skelaxin)
Another centrally acting drug, methocarbamol works as a skeletal muscle relaxant. However, the drugs efficiency and mechanisms are not well documented. A popular choice in muscle relaxants, it is used to treat acute pain from severe musculoskeletal conditions as well as muscle spasms.
How to take it: Recommended dosage of 800 mg three to four times daily. Tablets of 400mg and 800mg are available only by prescription, and are sold in generic forms as well as under the brand name Skelaxin.
Possible side effects: Unlikely side effects include dizziness, drowsiness, headache, nausea and dry mouth.
7. Methocarbamol (Marbaxin, Robaxin)
Methocarbamol uses an unknown mechanism that acts centrally as a muscle relaxant. A guaifenesin derivative, it is used to treat acute pain associated with musculoskeletal conditions.
How to take it: While taken alone as a generic or under the trade name Robaxin and Marbaxin, methocarbamol is prescribed in 500 and 750 mg tablets that are taken up to three to four times daily at a 1500mg dose.
Possible side effects: Blurred vision, drowsiness, headache, skin rash and nausea.
8. Orphenadrine (Flexon, Norgesic, Norflex)
Another centrally acting drug, orphenadrine is a nonopiate analgesic and muscle relaxant. This drug is a methyl derivative of diphenhydramine, which is common anti-histamine. While the effectiveness of this drug is better than fair, the mechanisms by which it works are unknown. This drug is commonly used for treating acute pain associated with musculoskeletal conditions and can be administered orally or parenterally.
How to take it: Available in generic form in standard and extended release tablets to be taken twice daily. You can also find orphenadrine sold under trade names like Norgesic, Norflex, Deenar, Banflex, Disipal and X-Otag. You can also find it under parenteral delivery methods as Flexoject and Myolin. Recommended dose for parenteral formulas are 60 mg delivered intravenously or intramuscularly, also done twice daily.
Possible side effects: Drowsiness, diaphoresis, flushing, dry mouth,confusion and impaired vision.
9. Tizanidine (Zanaflex)
Used to treat chronic spasticity and acute muscles spasms from a variety of causes, tizandidine is a centrally acting muscle relaxant that is derived from imidazoline. The mechanism by which tizanidine works is not well known, but it appears that it might act at the level of the spinal cord reflexes, most likely as an alpha-adrenergic agonist that inhibits the activity of the motor neurons.
How to take it: Only approved for short term use, it is prescribed in tablets and capsules in doses of 2, 4 or 6 mg to be taken three to four times a day. Tizanidine is available in many generic forms as well as under the trade name Zanaflex.
Possible side effects: Fatigue, drowsiness, dizziness, muscle weakness, dry mouth and occasional hypotension (low blood pressure).
Notes and Precautions
- Medications classified as muscle relaxants work best when they are taken at or before bedtime. A patient should not use them if they need to drive or operate machinery.
- Muscle relaxants can be habit forming, and are used for short periods to avoid dependency.
- If a patient has a personal or family history of hallucinations, delusions or any other psychiatric disorder, they should not use a cannabis extract based medication.
- People with stomach ulcers should not take baclofen.
- People with severe liver problems should not take tizanidine.
- Drowsiness is a common side effect in almost any muscle relaxer. Do not drive or operate machinery when suffering from drowsiness. People taking these medications should not consume alcohol.
- Medications like baclofen should be tapered instead of suddenly stopped. The dose should be gradually decreased under a doctor’s supervision before a patient stops taking it.