Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Stop using hydroquinone topical and call your doctor at once if you have:
severe skin redness, burning, or stinging;
severe skin dryness, cracking, or bleeding;
blisters or oozing; or
blue or black discoloration of the skin (especially if you are Hispanic or African-American).
Common side effects may include:
mild burning or stinging of treated skin; or
mild itching, redness, or other irritation.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Hydroquinone topical side effects (more detail)
