Questions I've been asked about drugs over the years:

Q: How do we know if we are reacting badly to a drug?
A: I can only list some of the symptoms I've read about in your letters and from personal experience. By paying attention to your body you'll know if something isn't right and it's then that you should get in touch with the prescribing physician or your pharmacist or, if it is really bad, go to the emergency department of your hospital. Some reactions can happen within 20 minutes, while other drugs can take days, weeks and months to slowly make our CMT worse.

Some quick reactions could be extreme coldness or flushing, inability to concentrate, blurry vision, fainting, nausea, cramping, an overall feeling of unwellness. Some, which can occur in hours or days, are numbness in extremities, even lips, tremor, muscle weakness, and these can progress into a complete exacerbation of your CMT if steps aren't taken. Remember, everyone is different, so if you are having an adverse reaction to a drug, you may not fit the possibles mentioned. If you feel that you are having a reaction, act on it, don't ignore it and suffer in silence. Your silence could mean the difference between catching a drug reaction and a much worsened case of CMT.

Q: Are the long-term, drug-caused symptoms reversible?
A: Most symptoms go away in hours or days after you stop taking the drug, but in some people who have taken a drug over a fairly long period, they can be left with much worse CMT than they had before they took the drug, and there is nothing they an do about it but wait and hope.

Q: If vitamin B6 (pyridoxine) can be toxic to us in large doses, how much is too much?
A: Dr. Bird answered this question a while back. "Large amounts of vitamin B6 can be toxic to nerves. The exact dose that is "too much" is not known. I would advise not taking more than 50mg a day."
Also remember that there is vit. B6 in foods (the highest are Brewer's Yeast, carrots, chicken, eggs, fish, meat, peas, spinach, sunflower seeds, walnuts and wheat germ) and check your other vitamins to make sure they don't have additional B6 added. A one-a-day type vitamin usually has a low amount of B6 in it. I'd say take as low a daily dose of vit. B6 as possible in your daily vitamins if you must take any at all. Vit. B6 in food is fine but don't supplement your diet with vit. B6. I know advice is often confusing and contradictory so why not play it safe and just take in what is in your food and maybe a one-a-day type vitamin.

Q: Are there any other harmful vitamins?
A: Mega-doses of any vitamin have the potential to harm. Vitamins A and D in large doses can be harmful to us but there hasn't been any real work done on it in conjunction with CMT.

K Potassium
Question from Esther Swain: When my husband was having the nerve and muscle biopsy surgery done, they discovered he had slightly lower than average levels of K. No amount of shots, pills or K-rich foods cold raise it. He just doesn't absorb the normal amount. The doctors were amazed. In talking to a friend of mine who is a medical student, I learned that K is essential for proper nerve function. Without it, nerve cells can't send out impulses correctly; in other words, they misfire. My question is: Do others with CMT have lower levels of K? Is it a cause or an effect of CMT? Does the body fail to absorb K because the nerve no longer needs as much or is K not being absorbed and thus adding to the malfunction of the nerve cells?
Answer from Dr. Orest Hurko, Associate Professor, Neurology and Medicine, The Center for Medical Genetics, The Johns Hopkins Hospital, Baltimore, MD. Potassium deficiency is not a feature of CMT. Potassium is not only required for proper function of nerves but also of the heart and skeletal muscle. Abnormalities of potassium most commonly result from diuretic medications but can also reflect hormonal imbalance, losses from diarrhea or certain benign tumors of the colon, as well as some type of kidney disease. If a patient has a significant abnormality in their potassium levels, it is important not only to treat the deficiency but also to identify the underlying problem. It isn't CMT.

Q: My husband's doctor prescribed Flagyl for an infection and his CMT got so much worse. I thought Flagyl was only for women's yeast infections.
A: Flagyl is used for all kinds of things. It is an antiprotozoal (will not let Protozoa, which can account for various infections, grow) and antibacterial agent and it is definitely one of the drugs that can make your CMT worse. My dog was put on it for recurring bowel inflammations. Flagyl can also be in over-the-counter remedies, so check the ingredients for Metronidazole before buying.

Q: I am a family physician caring for a CMT patient who is bipolar (manic depression). He has stopped his lithium due to info on the web that lithium is contra-indicated in CMT. Neither I nor his neurologist have found any medical literature describing such a contra-indication.
A: Dr. Thomas Bird answers this question:
This is one of those seemingly simple questions that turns out to be complex and sent me off to the medical library. Bipolar disorder (manic-depressive illness) is relatively common and lithium is a mainstay of therapy that is often critical to the patient's well-being. (This is impressively and poignantly described in "An Unquiet Mind" by Kay Jamison, Knopf, 1995.)
The key issues for your readers are: Does lithium cause peripheral nerve damage and is it dangerous to take if you have CMT? As best I can tell, thee is no clear cut answer. There have been a few reported instances of severe nerve damage in persons who have been intoxicated or overdosed with lithium. Thus, there is some evidence that it is a nerve toxin in high doses.

There is very little information as to whether it causes mild nerve damage in normally prescribed doses, but one 20-some-year-old article suggests that it might. Lithium rarely if ever appears on lists of peripheral nerve toxins and is often not even mentioned in textbooks of peripheral nerve disease. It looks like this may be an "obscure" area of interest in clinical neuroscience about which we need more information.

I would presently be reticent to tell someone with bipolar disorder and CMT not to take lithium, but on the other hand, there is some evidence for nerve toxicity, so I would keep doses on the low side and search for more information.

Q: My dentist wants to put a gold crown on two of my teeth. The list says gold is contra-indicated for CMT. What should I tell him?
A: The gold that is talked about on the list is gold injections that are sometimes given for severe arthritis or rheumatism, not gold fillings.

Q: I have many silver amalgam fillings that contain mercury. Will they make my CMT worse?
A: There are mixed opinions on this and it is up to you to decide what you want to do after you've read everything about it you can get your hands on about the topic. Obviously, the fewer mercury fillings the better. We asked the Canadian Dental Association for their input and they sent us a fax telling us where they stand along with some statements from Health Canada. These say that the evidence isn't there to suggest that mercury amalgam fillings have caused severe disease and nerve damage in people. Conclusion #2 which quotes the U.S. Public Health Service says: "Current evidence does not indicate that mercury contributes to Alzheimer's disease, amytrophic lateral sclerosis, multiple sclerosis or Parkinson's disease."

Health Canada advises that amalgam fillings not be used in the primary teeth of children or be placed in or taken out of the mouths of pregnant women.

The directive also says:"…the use of (Mercury) amalgam is to be decreased as much as possible in order to reduce the strain on the body caused by general mercury intake."

I'm wondering if, when the nervous system is already stressed because of our CMT, the addition of mercury fillings simply add to it and contribute to our overall condition. There has been no research. Should you purposely have them changed? It's up to you and if you think it can help and your pocketbook of course; it's a costly, time-consuming, uncomfortable affair but several of our people have said they think it has helped.

Q: Talking about dentistry, what about freezing? That's a drug isn't it?

A: Yes, several type of drugs are used in dental freezing and some may not work for you. See CMT and dentistry

Q: What about anesthetics for surgical procedures?
A: Anesthetics are drugs, and we've covered the whole question of preparing for surgery, anesthetics, everything. Look under Anesthetics.

Q: Are there any drugs that can help my CMT?
A: There is a type of CMT that responds to the drug Prednisone and that form is a progressive form of chronic inflammatory-demyelinating polyradiculoneuropathy, and in addition, people who have it experience all of the symptoms of hereditary motor and sensory neuropathy. Prednisone is not a cure and only helps this particular group

Q: Is there any way I can tell if a drug could be potentially harmful to me?
A: Talk to your doctor when he prescribes it and talk to your pharmacist when he fills the prescription. While your doctor may not take the time to look the drug up, your pharmacist most likely will. Look for the words "could cause peripheral neuropathy" in the drug description. I'm told that thousands of drugs have this line in their description because the drug companies must warn everyone of anything they think could happen, but if you worry about a drug on the list and its possible side effects, know that in almost all the conditions in which these drugs are used an alternative drug can be found.

Q: What about alcohol and tobacco…why are they on the list?
A: Doctors reiterate that alcohol is the worst thing we can take into our bodies on a regular basis. From shaky knees, numbness, tremors, confusion and almost instant DTs, the consumption of alcohol has made it abundantly clear to some people with CMT that they should not drink. Some people with CMT can drink, in moderation, with no problems but you should be aware that it is not the best thing to do for your CMT.