N-Acetylcysteine - Frequently Asked Questions Return to Index

Q.  Should I consult my doctor before trying NAC and vitamins.
Yes, it is highly recommended that you consult your neurologist or primary care physician before starting this or any treatment!

Q.  What does NAC stand for and what has it been used for in the past?
N-Acetylcysteine, has been used in the liquid form as an inhalation treatment for Cystic Fibrosis to thin mucus secretions.  It is also used to treat Tylenol overdose.

Q.  Where was the study done that started FA patients taking NAC?
University of Florida, reported Oct. 1995.

Q.  What is the recommended dosage of NAC and vitamins, according to the U of F Study?
NAC - 4-6 grams/day for adults and 60 mg/kg/day for children divided into 2-3 doses.

Suggested vitamin and mineral supplements (for adults) include:
Magnesium - 50-400 mg/ day  (don't take with the NAC)
Selenium - 100 mcg/day
Vitamin E (D-Alpha tocopheryl) - 400-800 U/day
Riboflavin (Vitamin B2) - 25-50 mg/day.

Q.  Are there any known (negative) side effects to taking this dosage of NAC?
Some have reported stomach upset, heartburn, or the feeling of increased appetite.

Q.  Are there any suggestions if I do experience stomach upset or heartburn?
Try taking the NAC on an empty stomach (like before your meal), with a large glass of water, juice, milk or soda.  Discontinue the NAC and let your doctor know if you are having any negative side effects.

Q.  Why should I not take the magnesium with my NAC?
It is thought that the NAC will counteract the absorbtion of the magnesium, if taken at the same time. 

Q.  What is the difference between liquid NAC (Mucomyst), compounded NAC, and  NAC purchased over the counter?
Mucomyst and NAC capsules that are compounded by a pharmacist are made with pharmaceutical-grade chemicals in a timed release formula that keeps the level of NAC in the bloodstream longer. Compounded NAC and liquid Mucomyst require a doctors prescription.  Over the counter NAC capsules are sometimes made with food-grade chemicals. If your insurance will cover Mucomyst, ask if they will cover compounded drugs.   It is generally agreed that the capsules are more pleasant to take, since the liquid form of Mucomyst has a strong odor and taste.  The capsules can be opened and sprinkled in applesauce for those who have trouble swallowing pills.  If your insurance won't pay for compounded NAC, try the over the counter variety.  Many have used this type with good results.

Q.  Where can I purchase NAC?  
See Where to Get

Q.  Is there any mail order willing to send NAC outside of the United States?
Yes, Personal Support Vitamins will ship Jarrow brand NAC, outside of the US.  
You must use a credit card to order and pay actual UPS charges.  No prescription is needed.

Q.  Is it OK to take all my NAC in the morning or evening?
It is most effective to divide your NAC in two or three doses, spread out over the day.

Q.  Do I begin taking a full dose of NAC?
You should begin at 1/4 dose and work up over a several weeks.

Q.  Are there any noticeable positive side effects?
Some do report a positive change in speech, strength, steadiness and swallowing (see: 1998 NAC Updates).   Many do not notice a physical change.  The HOPE is that the NAC will slow the progression of FA, and this is hard if not impossible to measure.

Q.  How long does it take to notice any positive effects?
If a patient does experience a positive effect or change in his physical condition, it is usually by the third or forth month.

The above FAQ was compiled by Sue Kittel as a result of questions and answers from various FA parents or individuals with FA, taking NAC.   This advice is from our own experience and a few documents from the University of Florida.  It shouldn't take the place of your own physician's advice and expertise.

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