Friday, November 9, 2012
Muscle Relaxants: Do they work for fibromyalgia?
Muscle Relaxants: Do they work for fibromyalgia? Your muscles are tight and achy. You may even feel ropy bands with firm knots in the mid-section of the muscle. These are myofascial trigger points, and their location often overlaps with the 18 tender points used for diagnosing fibromyalgia. Just pressing on them can send your pain through the roof. But can muscle relaxants ease the tension in your muscles and help untie (or at least loosen) your painful knots? The question of whether muscle relaxants can relieve your pain is complicated by the fact that this class of medications is very diverse, meaning that many drugs in this class vary substantially from the others. So some muscle relaxants might do the job better than others. Two fibromyalgia specialists offer advice on this topic based on their clinical experience, including which medications in this class they prefer and the doses they prescribe. See table below for more details. Robert Katz, M.D., of Rush University Medical Center in Chicago, IL, says: “Muscle relaxants do help reduce tenderness and may relax patients or ease their anxiety. I tend to prescribe Zanaflex and low dose Flexeril and use them quite often in the treatment of fibromyalgia. I tell patients I don’t want them sedated, but I also do not want their muscles so tender; I want their muscles relaxed. “I start with very low doses, sometimes half a tablet, and I see how the patient does on it. I try to give these medications during the daytime when patients have their greatest amount of pain and muscle tenderness. Muscle relaxants have a transient effect. This means that patients cannot take them at bedtime to reduce morning stiffness eight hours later. They must be on board when the patient has the most amount of pain. “I suspect that this class of medications somehow relaxes the central nervous system a bit and they also have a relaxing effect on the peripheral system (i.e., the muscles). It is somewhat like getting a massage. However, I have never been able to document how much these agents reduce muscle tenderness.” Richard Podell, M.D., of the UMDNJ-Robert Wood Johnson Medical School, with practices in Springfield and Somerset, NJ, offers the following advice: “Some patients find valium-type medications (i.e., benzodiazepines, including Klonopin and Xanax), Flexeril or Skelaxin useful for reducing muscle pain, stiffness, twitching, and spasms. Two muscle relaxants used in multiple sclerosis to treat muscle spasms, Zanaflex and Lioresal, are sometimes helpful in fibromyalgia, too. The major drawback for daytime use of these medications is sedation, with the exception of Skelaxin, because it does not effect the central nervous system. “With regards to dosing, I typically begin with 25 to 50 percent of the usual standard starting dose. Fibromyalgia patients as a group are very sensitive to medication side effects, necessitating that one start low and build up slowly. Otherwise, the initial drug effects are likely to bowl a patient over. “As to why these medications work, we know so little about drug mechanisms, I’ve learned to be quite humble. Some treatments should help in theory but they don’t and vice versa. More impressively, various drugs act one way in one person and the opposite in others, and it is not just people with fibromyalgia. It is well-known that benzodiazepine/valium-type relaxants cause sedation and relieve anxiety in most people, but produce activation and increased anxiety in a small yet significant subset.” Lowest Possible Doses In order to minimize daytime sedation and other side effects, Katz and Podell begin patients on the lowest possible dose. Here’s the rundown, with the generic name in parentheses: Highly Sedating •Flexeril (cyclobenzaprine): 5 mg (10 mg tablet cut in half) •Lioresal (baclofen): 5 mg (10 mg tablet cut in half) Benzodiazepines •Klonopin (clonazepam): 0.25 mg (0.5 mg tablet cut in half) •Valium (diazepam): 1 mg (2 mg tablet cut in half) •Xanax (alprazolam): 0.125 mg (0.25 mg tablet cut in half) Least Sedating •Skelaxin (metaxalone): 200 mg (400 mg tablet cut in half) •Zanaflex (tizanidine) : 1 mg (4 mg tablet is scored two ways)