Print This Post Print This Post

Sulfa Vs. Sulfites Vs. Sulfur Allergies – Confusing Terminology

Written by Wellness Club on April 7, 2009 – 9:25 pm -

Sulfa Vs. Sulfites Vs. Sulfur Allergies – Confusing Terminology

By Dr. Myatt

Someone wrote and asked me about Alpha-lipoic acid, to wit:

"I have had a life long allergic reaction to sulpha – it crystallizes in my urine, making urination difficult. I just started taking ALA as an aide for glaucoma. I am 60 yrs. old.

I understand that ALA is supha based. How should I proceed?

Thank you,


Hey Sal, there should be no problem with alpha lipoic acid, and “sulfa” (a drug) does not cause allergic reactions because of the sulfur content. Here’s the scoop.

Sulfur (chemical symbol: S) is a naturally occurring non-metallic element that comprises 0.25% of the human body. It is the 8th most prevalent element in the body. (A)

Elements found in the human body at their approximate amounts:

  • Oxygen (65%)
  • Carbon (18%)
  • Hydrogen (10%)
  • Nitrogen (3%)
  • Calcium (1.5%)
  • Phosphorus (1.0%)
  • Potassium (0.35%)
  • Sulfur (0.25%)
  • Sodium (0.15%)
  • Magnesium (0.05%)
  • Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%)
  • Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts)

Sulfur is an essential mineral, meaning that the body MUST have it. Sulfur is found in two amino acids, cysteine and methionine. Methionine is an essential amino acid. (B)

Sulfur is a component of many proteins, vitamins and hormones. Sulfur-containing compounds in humans include methionine, cysteine, homocysteine, cystathione, S-adenosylmethionine (SAMe), taurine, thiamin, biotin, alpha-lipoic acid (ALA), coenzyme A, glutathione (GSH), chondroitin sulfate, glucosamine sulfate, fibrinogen, heparin, metallothionein, and inorganic sulfate. (C)

There is no such thing as a sulfur allergy, just as there is no such thing as an allergy to oxygen , carbon or calcium, all of which also occur in the human body in high amounts. Anyone who was truly allergic to sulfur would be dead!

Sulfate (SO4) is a molecule which contains sulfur and oxygen. It occurs in nature and is found in most natural water including rain water. It is also the form of sulfur most commonly used to fertilize plants. (D) Sulfate may have a laxative effect that can lead to dehydration, especially in infants. Adults become “acclimatized” to high sulfate levels. (E).The current U.S. EPA national Secondary Maximum Contaminant Level for sulfate, is 250 mg/L (U.S. EPA, 1990).

Sulfite (SO3) is another molecule that contains sulfur. Sulfite is used on foods and some wines as antioxidants, and can cause asthmatic reactions. Sulfites are rare in medications.

Sulfites are used as preservatives on vegetables, especially vegetables in salad bars. This is probably the most common source of sulfite allergy reactions.

Sulfa drugs (sulfonamide class of antibiotics), contain sulfur but allergies and other reactions are not from the sulfur per se. Rather, the complex sulfonamine molecule can form proteins that are allergenic in some individuals. The sulfur atom is NOT the allergenic agent and being allergic to sulfa drugs does NOT imply having an allergy to sulfur.

Sulfa antibiotics include Septra®, Bactrim® and Pediazole®.

Go ahead, Sal, and take alpha-lipoic acid without concern for your history of sulfa drug allergy. And be sure to look for more in-depth information about proven treatments for glaucoma coming up in the next edition of HealthBeat News.

In Health,

Dr. Myatt


(A): Reference: H. A. Harper, V. W. Rodwell, P. A. Mayes, Review of Physiological Chemistry, 16th ed., Lange Medical Publications, Los Altos, California 1977.

B.) Reeds PJ. "Dispensable and indispensable amino acids for humans." J. Nutr. 130 (7): 1835S–40S, 2000.

C.) Parcell Stephen. Sulfur in Human Nutrition

and Applications in Medicine. Alternative Medicine Review Volume 7, Number 1 2002.

D.) Sulfate -vs- Elemental Sulfur Part I: There Is A Difference. Educational brochure by Agri-Facts ™

E.) Wilkes University Center for Environmental Quality,

Environmental Engineering and Earth Sciences.

“Sulfates and Hydrogen SulfideThat Rotten Egg / Sulfur Smell

Sulfate Reducing Bacteria “(SRB).

Print This Post Print This Post
SocialTwist Tell-a-Friend

Posted in Drugs and Alternatives, Health Questions | No Comments »

You must be logged in to post a comment.

Disclaimer: These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. No information on this website is intended as personal medical advice and should not take the place of a doctor's care.