Why does tretinoin cause purging?

What is happening inside the pores?

Acne starts when excess oil and dead skin cells block a hair follicle, the small opening where a hair grows. Bacteria can multiply in the blocked follicle and contribute to inflammation and pus. Washing the surface cannot remove the blockage inside, which is a disappointing plot twist for the cleansing aisle.45

Tretinoin belongs to a group of medicines called retinoids. Retinoids help normalize cell shedding inside follicles, reduce existing spots and prevent tiny early plugs called microcomedones from developing into new spots. They also reduce inflammatory activity. An early flare can happen during treatment, but tretinoin's longer term job is to prevent acne, not keep producing it.1

Does tretinoin cause purging?

Yes, tretinoin can cause an initial increase in acne spots. Worsening is particularly expected during the first 7 to 10 days, and retinoid treatment can make acne worse for a few weeks before improvement. Some spots improve after 2 to 3 weeks, while improvement can take more than 6 weeks.23

Early improvement is different from getting acne under control. Acne treatment commonly needs at least 6 to 8 weeks before fewer breakouts become noticeable, and topical retinoids can take 12 weeks or longer. Do not judge the final result by the first week's spot count. Follow your treatment plan rather than applying more medication to hurry it along.67

How should you use tretinoin during an early flare?

Use gentle cleansing, moisturizer and sun protection alongside your prescription.47

1. 1Wash your hands and the affected skin with a mild cleanser, then let the skin dry as directed.
2. 2At bedtime, apply a thin layer across the affected area, not just individual spots. Follow your prescribed schedule and keep tretinoin away from eyes, lips, nose corners and sunburned or eczema affected skin.
3. 3Use moisturizer for dryness. Your dermatologist can advise whether applying moisturizer before tretinoin, using a smaller amount or applying it less often would help irritation. Make those changes with their help.
4. 4During the day, seek shade, wear protective clothing and use sunscreen with broad spectrum protection, SPF 30 or higher and water resistance.

Do not add other topical medicines, including benzoyl peroxide or salicylic acid, unless your prescriber directs you to. Avoid scrubbing and picking spots. For dry skin, a fragrance free, water based moisturizer is an option.345

When should you contact your doctor?

Do not assume every new rash or uncomfortable reaction is purging. Retinoids can cause irritation with redness, peeling and dryness. Tell your doctor about severe or persistent burning, stinging, swelling or blistering. Call immediately for a rash, hives, or pain or discomfort at the treatment area. Persistent irritation despite reducing application frequency needs review.237

Arrange a review if acne is not improving, or spots become deep, painful or leave scars. Severe acne with nodules or cysts should not be managed with a topical retinoid alone. An unusual eruption also needs assessment because not every spot is acne.247

Tell your prescriber about eczema, previous retinoid irritation and all other medicines you use. Discuss pregnancy, plans to become pregnant or breastfeeding before treatment; if you become pregnant while using tretinoin, call your doctor.36