Summary Safety Review - Alpha Lipoic Acid - Assessing the Potential Risk of Low Blood Sugar (Hypoglycemic Episodes)

June 30, 2016

Product

Alpha lipoic acid-containing natural health products.

Potential Safety Issue

Low blood sugar (hypoglycemic episodes)

Key Messages

• Alpha lipoic acid is an ingredient in some natural health products and is used as an antioxidant for the maintenance of good health and/or to promote the healthy breakdown of glucose.
• Health Canada carried out a safety review with case reports of hypoglycemic episodes linked with the use of alpha lipoic acid that were published in the scientific literature.
• Health Canada's review concluded that alpha lipoic acid may cause a condition known as IAS (insulin autoimmune syndrome), which can result in low blood sugar (hypoglycemia) in individuals with a specific genetic variation. The cases of hypoglycemia resolved once the alpha lipoic acid was stopped.
• Health Canada is therefore considering updates to the labelling standard for alpha lipoic acid to inform consumers to stop using it and consult a healthcare professional if they experience symptoms of low blood sugar such as sweating, paleness, chills, headache, dizziness and/or confusion. In addition, Health Canada will publish a Health Product InfoWatch article to raise awareness of this potential risk.

Overview

This safety review was carried out by Health Canada after the publication of case reports of IAS (insulin autoimmune syndrome) causing hypoglycemic episodes linked with the use of oral alpha lipoic acid products in individuals with a genetic variation which causes the body's own defence system to attack insulin (insulin autoimmune syndrome).

Use in Canada

• Alpha lipoic acid is a medicinal ingredient in some natural health products and is used as an antioxidant for the maintenance of good health and/or to help promote the healthy breakdown of glucose. It is also used as a preservative (non-medicinal ingredient) in some natural health products.
• At the time of the review, Health Canada had licensed over 800 natural health products containing alpha lipoic acid, also known as thioctic acid, as a medicinal ingredient for human use.

Safety Review Findings

• At the time of the review, there were no Canadian reports of hypoglycemic episodes reported with the use of alpha lipoic acid.
• There are several published international case reports of hypoglycemic episodes in individuals with IAS (insulin autoimmune syndrome) which may have been triggered by the use of oral products containing alpha lipoic acid. The cases of hypoglycemia resolved once the alpha lipoic acid was stopped.
• There is scientific evidence linking a genetic predisposition for IAS (insulin autoimmune syndrome) with the risk for developing hypoglycemic episodes with the use of oral alpha lipoic acid.
• Although most of these cases originate from Asia where these genetic variations are more common, cases have recently been reported in Europe as well. It is not known how common this specific genetic variation is within the Canadian population, which is multi-cultural and genetically varied.

Conclusions and Actions

• Health Canada's safety review concluded that alpha lipoic acid may cause a condition known as IAS (insulin autoimmune syndrome), which can result in low blood sugar (hypoglycemia). This side effect seems to be rare and the reported cases happened in individuals with a specific genetic variation. The cases of hypoglycemia resolved once the alpha lipoic acid was stopped.
• Consumers may not be aware of the risk until they are exposed to alpha lipoic acid, therefore Health Canada is considering updates to the labelling standard for alpha lipoic acid to inform consumers to stop using the product and to consult a healthcare professional if they experience symptoms of low blood sugar such as sweating, paleness, chills, headache, dizziness and/or confusion.
• In addition, Health Canada will publish a Health Product InfoWatch article to raise awareness of this potential risk.
• Health Canada will continue to monitor safety information involving alpha lipoic acid, as it does for all health products on the Canadian market, to identify and assess potential harms. Health Canada will take appropriate and timely action if and when any new health risks are identified.

Additional Information

The analysis that contributed to this safety review included scientific and medical literature, Canadian and international adverse reaction reports and what is known about the use of this drug both in Canada and internationally.

For additional information, contact the Marketed Health Products Directorate.