• Hydroquinone is a skin-lightening agent. It bleaches the skin, which can be helpful when treating different forms of  that is used to lighten areas of darkened skin such as freckles, melasma, age spots, and acne scars.
• The FDA has confirmed that hydroquinone can be safely sold over the counter (OTC) in 2 percent concentrations.
• Hydroquinone bleaches your skin by decreasing the number of melanocytes present. Melanocytes make melanin, which is what produces your skin tone.
• In cases of hyperpigmentation, more melanin is present due to an increase in melanocyte production. By controlling these melanocytes, your skin will become more evenly toned over time.
• It takes about four weeks on average for the ingredient to take effect. It may take several months of consistent use before you see full results.

Hydroquinone is used to treat skin conditions related to hyperpigmentation. This includes:

• Acne scars
• Age spots
• Freckles
• Melasma
• Post-inflammatory marks from psoriasis and eczema

Get emergency medical help if you have any of these 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.

In rare cases, hydroquinone has caused a condition called ochronosis. It’s marked by papules and bluish-black pigmentation. This can occur after prolonged daily use. As such, you shouldn’t use products with this ingredient for more than five months at a time.

• You should not use this medicine if you are allergic to hydroquinone or peroxide.

Ask a doctor or pharmacist if it is safe for you to use this medicine if you have other medical conditions, especially:

• Liver or kidney disease;
• Asthma or sulfite allergy; or
• If you are using any antibiotic medicine.

It is not known whether hydroquinone topical will harm an unborn baby. Do not use this medicine without a doctor's advice if you are pregnant.

It is not known whether hydroquinone topical passes into breast milk or if it could harm a nursing baby. Do not use this medicine without a doctor's advice if you are breast-feeding a baby.

Do not give this medicine to anyone under 12 years old without medical advice.