Retinol creams, also known as topical retinoids, are derivatives of vitamin A that are used to treat mild to moderately severe acne. Retinoids are primarily effective at unclogging pores and preventing new blackheads and whiteheads, or comedones, from forming. This prevents future acne breakouts. Tazarotene, adapalene and tretinoin are three topical retinoids that are available by prescription.

Tazarotene

Tazarotene is a synthetic retinoid that is available in cream or gel form. It reduces and prevents acne by keeping the pores clear and reducing redness. According to the Mayo Clinic, tazarotene is also effective at treating psoriasis. If you are a woman of childbearing age, you will need to use reliable contraception to avoid pregnancy. Tazarotene has been shown to cause birth defects in animal studies. Avoid excessive exposure to sunlight and extreme heat or cold if you're taking tazarotene, because your skin may become more sensitive to extreme temperatures or sunlight. Side effects of tazarotene include redness or irritation of the skin. Speak with your physician if you experience extreme stinging or burning of the skin, changes in skin color, deep grooves or lines in the skin, severe dryness, itching or peeling of the skin, and pain or swelling of the skin.

Adapalene

Adapalene is a synthetic retinoid that is available in cream or gel form. According to the American Academy of Dermatology's AcneNet, it is effective at unclogging pores and has moderate to potent anti-inflammatory effects. If you're taking adapalene, your acne may worsen during treatment before it improves, which may take eight to 12 weeks. Side effects of adapalene treatment include redness, scaling, dryness, burning, stinging and itching. These side effects are more likely to occur at the start of treatment and subside as your skin adjusts to the medication. If side effects cause extreme discomfort or do not improve, contact your physician.

Tretinoin

Tretinoin was the first retinoid developed for topical use in treating acne. Unlike tazarotene and adapalene, it is a natural retinoid. It primarily works to unclog pores and prevent new clogs from forming. Tretinoin is a class D medication in pregnancy, which means that studies in pregnant women have shown a risk to the developing fetus. Notify your physician if you are pregnant or planning to become pregnant. Side effects of tretinoin use include redness or irritation of the skin. When applying, spread the medication away from the corners of your mouth, nose and eyes to avoid irritating these areas. More severe side effects include burning or stinging of the skin, lightening of the skin in treated areas, and severe peeling, redness or dryness of the skin. If you experience any of these side effects, contact your physician.