What's the Difference Between Tretinoin and Isotretinoin?

Tretinoin and isotretinoin are the sound-alike generic names for two different medications. Both medications are used to treat acne, and they both belong to a group of medications called retinoids. Retinoids are medications that are derived from vitamin A. But despite the similar names, tretinoin and isotretinoin medications are not interchangable when it comes to treating acne. They are used in different ways and for different reasons.

The confusion around tretinoin and isotretinoin isn't just the sound-alike names, but because there are some similarities between the two medications. Both medications are:

• Prescription-only medications
• Used to treat acne
• Derived from vitamin A
• Similar in their molecular make up

• Tretinoin is used topically to treat acne, while isotretinoin is used orally.
• Tretinoin is used to treat mild to moderate acne, but it's also used to treat age spots, sun damage and wrinkles.
• Isotretinoin is prescribed for severe or stubborn inflammatory acne. It does not improve signs of aging or hyperpigmentation.
• Tretinoin is used long-term to clear and keep acne away. Isotretinoin is used for short courses, and once acne is gone you stop using the medication.

Tretinoin is the active ingredient in medications prescribed to treat mild pimples to moderate acne and blackheads. Some easily recognizable brand names for drugs containing tretinoin include Retin-A, Retin-A Micro, Renova, Tretin-X, and Ziana.

These medications are used topically, so they are applied directly to the skin typically once or twice a day. Topical tretinoin medications come in cream, ointment, and gel.

Tretinoin helps to clear acne by speeding up the rate at which skin cells turn over (die and regenerate). This helps to unclog pores, clearing blackheads and inflamed pimples. Topical tretinoin is also used after acne has cleared up, to keep it away and prevent future breakouts.

The typical side effects of tretinoin include dry skin, peeling, and redness. It hasn't been studied extensively in pregnant women, though, so if you're pregnant topical tretinoin isn't the best acne treatment choice for you.

Isotretinoin is an oral medication, so rather than apply it to your skin you'll swallow it in pill form. It's most often prescribed for severe forms of acne. It's also used to treat milder cases that are stubborn and have not responded to other types of acne medication, and in cases when acne is leaving behind scars.

Until 2009, isotretinoin was available in the United States by the brand name Accutane. Today it's sold as Absorica, Amnesteem, Claravis, Myorisan, and Zenatane, and generic isotretinoin.

Unlike with tretinoin (and most acne medications, really) isotretinoin is only used for a finite length of time. In fact, most people only need one or two courses in their lifetime. Although in very specific cases, a low-dose of isotretinoin may be prescribed long-term.

Isotretinoin clears up acne, and in the majority of cases it stays away even after you stop using it. It's the closest thing we have to an actual cure for acne.

Isotretinoin is a very beneficial treatment for certain people, but it isn't right for everyone. It can cause side effects, some of which are potentially serious. Your doctor will monitor your skin and health during the entire time you're using isotretinoin. Know that most serious side effects are very rare.

Isotretinoin can't be used by pregnant women because it causes severe birth defects. The drug also increases the risk of miscarriage and premature birth.

Anyone taking isotretinoin must first register with a program called iPledge Program. The goal of this program is to prevent fetal exposure to isotretinoin. Everyone must register, even men and women who can't get pregnant, although requirements are different than those for women who can get pregnant.

The requirements include using two methods of contraception or practicing complete abstinence during treatment, having negative pregnancy tests each month (for women of childbearing potential), seeing a doctor monthly, and submitting to regular blood tests as needed.

A Word from Verywell

Although they have very similar-sounding names, isotretinoin and tretinoin are very different medications. Your dermatologist will help you decide if either is the right treatment option for your acne.

There are many other acne treatments available, too. These can be just as effective and may be a better fit in your case. The bottom line, though, if you need help treating acne call a dermatologist. There are many treatment options that can help you get clearer skin.