Inverse Psoriasis: Psoriasis in Skin Folds and the Genital Area
What psoriasis in skin folds and on the genitals looks like, what it can be confused with and how it's treated.
Part of our psoriasis guide.
Get urgent help first. Call 999 or go to A&E if your skin suddenly becomes red and inflamed over most of your body, or you have widespread pus-filled spots, especially with a fever, chills or feeling very unwell. These can be signs of erythrodermic or generalised pustular psoriasis, which are emergencies. See a GP soon if you have painful, swollen joints. Online treatment isn't suitable in these situations.
Key fact: inverse psoriasis causes smooth, red patches with little scale in skin folds such as the armpits, groin and under the breasts. It's treated with emollients and a mild or moderate steroid for no more than 2 weeks.
Adults only online, and not in pregnancy or breastfeeding. Access Doctor's online psoriasis service is for adults aged 18 and over, and can't supply treatment if you're pregnant or breastfeeding: your GP or midwife can help. Children with psoriasis should see their GP.
What is inverse psoriasis?
Inverse psoriasis (also called flexural psoriasis) affects skin folds: the armpits, groin, under the breasts, between the buttocks, behind the knees and in the folds of the tummy. Because these areas are warm and moist, the patches are usually smooth, shiny and red (or darker on brown and black skin) with little or no scale. They can be sore and are often made worse by sweating and friction.
Our online service doesn't supply psoriasis treatment for the face, genitals or skin folds. These areas need an in-person assessment and gentler treatment, so please see your GP or pharmacist. We can help with psoriasis on the body, arms and legs.
What can be mistaken for inverse psoriasis?
| Condition | How it differs |
|---|---|
| Thrush (candida) or intertrigo | Red, moist rash in folds, often with small "satellite" spots at the edge. Can occur alongside psoriasis. |
| Fungal infection (tinea cruris) | Spreading edge, often itchy, usually in the groin; spares the scrotum. |
| Seborrhoeic dermatitis | Greasy, yellowish scale; often also on the scalp and face. |
| Erythrasma | Brown-pink patches in folds caused by bacteria. |
Because these rashes look alike and can occur together, it's worth getting a diagnosis before treating. A GP may take a swab or skin scraping.
How inverse psoriasis is treated
1
Soap substitute and emollient
Wash with an emollient instead of soap, pat dry gently and apply a light emollient.
2
Mild or moderate steroid, up to 2 weeks
NICE recommends a mild or moderate steroid once or twice a day for no more than 2 weeks for psoriasis in skin folds and the genital area.
3
Treat any infection
If thrush or bacteria are also present, a prescriber may use a combined cream containing a mild steroid with an antifungal.
4
If it keeps coming back
A specialist may use a non-steroid treatment such as tacrolimus ointment (off-label), or a vitamin D treatment, which can irritate folds.
Avoid in skin folds: potent steroids, Enstilar, Dovobet, coal tar and dithranol. Skin folds absorb more medicine, and these can cause thinning, stretch marks and irritation.
Genital psoriasis
Psoriasis can affect the vulva, penis, scrotum and the skin around the anus. It's common and not sexually transmitted. On the genitals it's usually smooth and red rather than scaly. Treatment is the same gentle approach: emollient as a soap substitute and a mild steroid for short courses on a doctor's advice.
- Sex isn't harmful, but friction can trigger a flare. A lubricant can help; check it's compatible with condoms.
- Wash off creams before sex and use a condom if a cream may still be on the skin, as some products can weaken latex.
- Wear loose, cotton underwear and avoid perfumed products.
- Talk to your GP or a sexual health clinic if you're not sure what the rash is.
Day-to-day tips for skin folds
- Keep folds clean and dry; dry gently after washing.
- Wear loose, breathable clothing.
- Use a fragrance-free emollient and avoid perfumed products and deodorants on affected skin.
- If you're overweight, losing weight reduces friction and can improve psoriasis.
UK safety and reporting side effects
Prescription psoriasis treatments are only supplied after a GPhC-registered pharmacist independent prescriber reviews your consultation, including where your psoriasis is, how much skin it covers and what you have used before. Always read the patient information leaflet. Since 2024, UK steroid packs show their strength on the front (mild, moderate, strong or very strong). The MHRA advises using topical steroids for the shortest time needed, and to tell a healthcare professional if your skin flares badly after you stop a steroid you have used for a long time, which can be a topical steroid withdrawal reaction.
If you think you've had a side effect, tell your pharmacist or doctor. You can also report it to the MHRA through the Yellow Card scheme.
Getting help with psoriasis
For psoriasis in skin folds or the genital area, please see your GP or a sexual health clinic. If you also have psoriasis on your body, arms or legs, our pharmacist prescribers can assess that online: see our psoriasis treatment page.
Frequently Asked Questions
What does inverse psoriasis look like?
Smooth, shiny, well-defined patches in skin folds, usually red on white skin and darker on brown and black skin, with little or no scale. They can be sore, especially with sweating and friction.
Does inverse psoriasis go away?
It can clear with treatment, but like other psoriasis it tends to come back. Keeping folds dry, using emollients and treating flares early helps.
What triggers inverse psoriasis?
Friction, sweating, heat and being overweight are common triggers, as well as the usual psoriasis triggers such as stress and infection. Thrush in the folds can also make it worse.
What can be mistaken for inverse psoriasis?
Thrush (candida), intertrigo, fungal groin infections, seborrhoeic dermatitis and erythrasma can all look similar, and some can occur alongside psoriasis. A GP may take a swab to check.
Is genital psoriasis an STI?
No. Genital psoriasis is not sexually transmitted and can't be passed on. If you're not sure what a genital rash is, see your GP or a sexual health clinic.
References
- NICE. Psoriasis: assessment and management (CG153). nice.org.uk
- NICE Clinical Knowledge Summaries. Psoriasis. cks.nice.org.uk
- British Association of Dermatologists. Psoriasis: an overview (patient information leaflet), August 2023. skinhealthinfo.org.uk
- NHS. Psoriasis. nhs.uk
Medical disclaimer: This article is for information only and isn’t medical advice. Prescription psoriasis treatments need a clinical consultation before they can be supplied. If your skin is red all over, you have widespread pus spots, a fever or you feel unwell, seek medical advice the same day. In a medical emergency, call 999.