Alpha-lipoic acid, sometimes referred to as ALA, is an antioxidant produced in small amounts by the body. It helps cells generate energy and purifies metabolic waste products called free radicals. Alpha-lipoic acid is taken as a dietary supplement, because some preliminary evidence suggests it might support brain function, help regulate blood sugar and relieve nerve damage from diabetes. However, the effectiveness of oral ALA for these conditions remains unproven in human studies. Side effects from ALA supplements are uncommon and generally occur when high doses have been taken. Gastrointestinal upset, particularly nausea, is the most common complaint. Heartburn may occur too, but there are remedies for this.
Take With Food
ALA supplements are available as tablets and capsules. It is not known why ALA causes heartburn in some people. As with other medications that can cause stomach upset, taking alpha-lipoic acid with a snack may be helpful. However, the rate of absorption of ALA on an empty stomach is only 30 to 40 percent, according to a November 2014 article in "Clinical Pharmacology." Taking ALA with food has been shown to diminish absorption from the intestines. It's best to avoid taking ALA with carbonated drinks, because belching and reflux might occur.
Over-the-counter antacids are the fastest way to get short-term relief from a severe attack of heartburn -- they neutralize acid in the stomach on contact. Liquid antacids usually work the fastest, but all antacids typically take effect within a few minutes. It is possible that, as with food, antacids could interfere with ALA absorption, though there is no research confirming this.
Certain medications taken before ALA supplements may help prevent heartburn. Acid blockers known as H2 inhibitors take effect within 30 to 60 minutes and reach their peak effect at one to two hours. It's not known if H2 blockers interfere with ALA absorption, though this is unlikely. Over-the-counter H2 blockers include famotidine (Pepcid), cimetidine (Tagamet), ranitidine (Zantac) and nizatidine (Axid). These medicines can also be taken after heartburn develops. H2 blockers can be taken with antacids, and combination products are available.
Warnings and Precautions
Before taking ALA, consult your health-care provider about its safety and possible interactions with other medications you may be taking. If ALA supplements cause heartburn, talk with your provider about whether it is appropriate to continue. Other reported side effects include fatigue, insomnia, skin rash and diarrhea. ALA might cause blood sugar levels to drop, so people with diabetes should consult with their health-care providers before taking it. People deficient in thiamine, which is associated with long-term alcohol abuse, should not take alpha-lipoic acid. It is not known whether ALA is safe for pregnant and breastfeeding women.
Frequent or troublesome heartburn could be gastroesophageal reflux disease, a possibly serious condition that calls for medical evaluation.
Medical advisor: Jonathan E. Aviv, M.D., FACS
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- Integrative Medicine, Second Edition; David Rakel, M.D.
- University of Maryland Medical Center: Alpha-Lipoic Acid
- Lipoic Acid: Energy Production, Antioxidant Activity and Health Effects; Mulchand S. Patel and Lester Packer
- Expert Review of Clinical Pharmacology: Acid Peptic Diseases: Pharmacological Approach to Treatment
- Oregon State University Linus Pauling Institute Micronutrient Information Center: Lipoic Acid
- Merck Manual Professional Version: Drug Treatment of Gastric Acidity
- Clinical Pharmacology: Enantiomer-selective Pharmacokinetics, Oral Bioavailability, and Sex Effects of Various Alpha-Lipoic Acid Dosage Forms