Alpha Hydroxy Acids
How does Alpha Hydroxy Acids work?
Alpha hydroxy acids seem to work by removing the top layers of dead skin cells. They can also increase the thickness of deeper layers of skin, promoting firmness.
Are there safety concerns?
Alpha hydroxy acids at a concentration of 10% or less as a lotion or cream are LIKELY SAFE
for most people when applied to the skin appropriately and as directed. In some people, alpha hydroxy acids can make the skin extra sensitive to sunlight. Be sure to use a sunscreen
while using alpha hydroxy acid products.
Alpha hydroxy acids can also cause mild skin irritation, redness, swelling, itching
, and skin discoloration.
Facial peels, lotions, and creams with a concentration greater than 10% should only be used under the supervision of a dermatologist. Facial peels can cause moderate to severe skin irritation, redness, and burning. Facial peels left on the skin for periods longer than recommended can cause severe burns
to the skin.
When taken by mouth, the alpha hydroxy acid called malic acid is POSSIBLY SAFE
when used short-term. Some people can have side effects including diarrhea
, and general stomach discomfort.
Special Precautions & Warnings:
Pregnancy and breast-feeding
: Alpha hydroxy creams at a concentration of 10% or less are LIKELY SAFE
when applied to the skin during pregnancy and breast-feeding. But don't take malic acid (the form of alpha hydroxy acids that is generally taken by mouth). Not enough is known about the safety of malic acid during pregnancy and breast-feeding.
: Alpha hydroxy acids can worsen skin conditions
by causing skin irritation and removal of the top layer of skin cells.
Dosing considerations for Alpha Hydroxy Acids.
The following doses have been studied in scientific research:
APPLIED TO THE SKIN
- For treating skin wrinkled and aged by sunlight: Alpha hydroxy acid products containing lactic acid, tartaric acid, gluconolactone, or glycolic acid (GA) in 8% concentration are used. The alpha hydroxy acid gluconolactone has also been used in a 14% solution. These products are usually applied to the skin twice daily.
- For improving the appearance of acne scars: glycolic acid (GA) facial peels are used. Peels of increasing strength of 20%, 35%, 50%, and 70% are applied every two weeks. Peels are applied first for 2 minutes and then for a longer time (up to 4-5 minutes) before applying the next stronger solution. Completing the series at least 6 times is usually needed before skin looks better. People who do not like facial peels often use 15% GA lotion daily long-term instead.
- For lightening brown patches due to a condition called melasma: a 10% lotion of the glycolic acid (GA) is applied with a sunscreen to facial skin nightly for 2 weeks. Then a peeling program is done monthly for 3 months in a row. The peeling program features a 50% GA peel applied three times to the face and left on for a period of 2-5 minutes each time (first peel 2 minutes, second peel 4 minutes, and third peel 5 minutes).