A daily dose of up to 600 milligrams of ALA is well tolerated by the human body. No adverse effects were observed on administration of 1,200 mg/day (600mg, 2 times/day) for 2 years and 1,800 mg/day (600 mg, 3 times/day) for 3 weeks in diabetic neuropathy patients under medical supervision. However, because of lack of long-term safety studies, ALA should not be administered to pregnant or lactating women.

Supplemental ALA may lower blood glucose levels (hypoglycemia) in individuals suffering from diabetes and/or impaired glucose intolerance. To avoid hypoglycemia, it is essential to adjust antidiabetic drug doses and monitor blood glucose level. High doses of ALA compete with biotin, and therefore it is essential to administer a dose of biotin along with ALA. A very high dose of ALA may also cause mild stomach upset.

In rare cases ALA has been reported to trigger an allergic reaction. It may cause itching, swelling in the face or hands, chest tightness, trouble breathing, or rash. Other possible Side Effects that ALA might cause include headache, muscle cramps, and a feeling of pins and needles in the body. If any of these adverse events show their presence, the ALA dose should be revised or discontinued for health reasons.

It should be noted here that ALA is a naturally occuring anti-oxidant in the human body. It is also gleaned for supplmental use from brocolli, spinach, and tomatoe, as well as beef, yeast, and kidneys. It has been widely celebrated as a general, all-around health supplement around the world.