- How to Spot and Treat Inverse Psoriasis
- Onset and Symptoms
- Treatment Options
- 5 Natural Treatments for Inverse Psoriasis
- What to know about genital psoriasis
- How can I treat genital psoriasis?
- What Does Inverse Psoriasis Look Like?
- What Is Inverse Psoriasis?
- What Causes Inverse Psoriasis?
- Inverse Psoriasis Treatment
How to Spot and Treat Inverse Psoriasis
Inverse psoriasis is a painful and difficult type of psoriasis that forms in the body’s skin folds, such as the armpits, genitals, and under the breasts or buttocks. Because these skin folds are called flexures, it also is known as flexural psoriasis.
This type of psoriasis is the inverse — or opposite — of the more common plaque psoriasis, which occurs on the outer, extensor surfaces of the body, such as the knees and elbows.
Psoriasis, in general, is a genetic condition passed down through families. “It’s likely that multiple genes need to be affected to allow psoriasis to occur, and that it’s frequently triggered by an external event, such as an infection,” says James W. Swan, MD, professor of dermatology at the Loyola University Stritch School of Medicine in Maywood, Illinois. In the case of inverse psoriasis, the triggers also involve friction and dampness, and are associated with sweating.
Inverse psoriasis occurs in 2 to 6 percent of people with psoriasis and most often alongside some other form of the condition, such as plaque psoriasis. It’s more common in people who are overweight or obese or have deep skin folds. People who are middle-aged or seniors are more likely to develop flexural psoriasis than younger people.
Onset and Symptoms
The first signs of inverse psoriasis are bright, red patches of skin in body folds. These lesions tend to be shiny and smooth — the moistness of the affected area prevents the development of the dry skin scales that accompany other types of psoriasis.
Inverse psoriasis can be one of the most painful and irritating forms of the disease, due to the location of the lesions around the genitals and armpits and underneath the breasts and buttocks. The affected skin becomes very tender, and is further irritated by sweating and skin rubbing against itself. Sometimes a crease in the center of an inverse psoriasis lesion will crack open, creating the possibility of bleeding or infection.
Treatment of inverse psoriasis is difficult due to the location of the lesions. Skin folds often prove to be some of the most sensitive skin on the body, which increases the risk of a reaction to many of the topical drugs available for psoriasis treatment. Doctors often must treat not only the psoriasis, but also accompanying infections caused by yeast or fungus.
Inverse or flexural psoriasis treatments include:
Corticosteroids These topical medications suppress the immune system and reduce inflammation, but also can cause thinning of the skin and must be used carefully on the already-thin skin located in skin folds. If the patient has tested positive for infection, doctors will sometimes use diluted topical steroids mixed with other medication — for example, a 1 or 2 percent hydrocortisone cream blended with anti-yeast or anti-fungal medicine.
Calcipotriene This cream or ointment contains a synthetic form of vitamin D3 that can slow skin cell turnover. It can irritate the skin, too, so it must be used carefully in treating flexural psoriasis. It isn’t recommended for use on the genitals.
Coal Tar This soothing agent comes in gels or ointments that can be applied to lesions. It also is available as a liquid that can be added to bath water to help relieve symptoms.
Castellani’s Paint This product, with the active ingredient phenol, can be prescribed or bought over the counter under the brand name Castederm. It’s a liquid that is painted on and can help dry lesions in skin folds that have become moist.
Light Therapy Also known as phototherapy, this involves exposing lesions to ultraviolet light, either through natural sunlight or by spending time under a sun lamp. You may be prescribed a medication to accompany the light therapy, to enhance the body’s response.
Systemic Medication People with severe inverse psoriasis may need to take pills or receive injections to help treat their symptoms. Options include immunosuppressive medicines, like Trexall (methotrexate) and Restasis (cyclosporine), or biologic drugs that target specific immune reactions.
While inverse psoriasis is very painful, there are several approaches to treating it. Talk with your doctor or dermatologist about the best way to ease your symptoms and find relief.
5 Natural Treatments for Inverse Psoriasis
You may want to consider natural treatments to complement prescribed medications or to reduce the chance of a psoriasis flare-up. There are many natural options you can try that can help your psoriasis symptoms. Scientists haven’t proven that all of these treatments work.
It’s important to speak with your doctor before trying any new treatments, including natural treatments. They may react with medications or other treatments you’re using.
1. Healthy lifestyle habits
One way to manage psoriasis is to adopt a healthy lifestyle. Obesity and a poor diet can worsen the condition. A study in the British Journal of Dermatology found that losing weight could help improve psoriasis. Losing weight can also make psoriasis treatments more effective.
Simple ways to be healthier include:
- incorporating whole foods into your diet, such as fruits and vegetables
- eating lean meats and other healthy proteins
- reducing your intake of sugar and other processed foods
You should also exercise to lose or maintain a healthy weight.
2. Herbal therapies
Some people believe that certain herbal therapies can treat psoriasis. A study published in the American Journal of Clinical Dermatology found evidence that Mahonia aquifolium may be an effective psoriasis treatment. M. aquifolium is a species of grape found in Oregon. A 10 percent concentration of the plant may help mild to moderate psoriasis. You should only use it topically unless you’re using it an alternative way under the direction of your doctor.
There’s also some evidence that aloe vera, neem, and sweet whey extracts may help psoriasis.
There are other herbal therapies that may work. You can try apple cider vinegar or tea tree oil to treat scalp psoriasis. Ingesting 1.5 to 3 grams (g) of turmeric per day may reduce psoriasis symptoms.
3. Nutritional supplements
Evidence suggests that nutritional supplements can help psoriasis symptoms. However, the U.S. Food and Drug Administration doesn’t regulate nutritional supplements. Brands of supplements can vary widely. If you experience any side effects from using nutritional supplements, stop using them.
The following supplements may help treat psoriasis symptoms:
- fish oil
- vitamin D
- vitamin B-12
You should only take fish oil supplements in small doses. Taking more than 3 g per day can impact blood clotting, thin your blood, and lower blood pressure. Side effects include an unpleasant aftertaste, heartburn, and nausea.
Vitamin D is in many foods, such as salmon, vitamin-D fortified drinks like milk and orange juice, and eggs. You can also get vitamin D from sunlight, though you should only get exposure to sunlight for 10 minutes at a time.
4. Mind-body interventions
Stress is a recognized trigger for psoriasis and other autoimmune conditions. There are several methods you can use to incorporate mind-body practices into your daily life:
- Practice aromatherapy. Use certain oils, such as chamomile, rose, and lavender, in a diffuser or a bath to reduce stress.
- Meditate by yourself or in a group setting for just a few minutes per day or longer.
- Practice mindfulness to reduce stress and increase your tolerance for physical and emotional pain caused by psoriasis.
5. Destination treatments
Evidence suggests that bathing in natural springs and being exposed to sunshine can alleviate psoriasis symptoms. This is known as balneotherapy or balneophototherapy. The Dead Sea in the Mediterranean is known for its healing qualities because it has a high percentage of salt in its water and its elevation below sea level provides optimal sunlight.
There are some hot springs and mineral springs in the United States where you can get this treatment.
What to know about genital psoriasis
Treating flare-ups of genital psoriasis can be challenging. However, they typically respond well to remedies and soothing options. They might even resolve without treatment.
The condition is chronic, however, and a person can never fully cure it. That said, new biologic medications that target the autoimmune cause at the root of psoriasis can provide a long-term solution for symptoms and flares.
People should use topical creams carefully to avoid extra thinning of the skin and the formation of stretch marks.
Relieving an itch can be relatively uncomfortable, but treating lesions is more complicated. People must constantly moisturize the affected area and use topical treatments or ultraviolet (UV) light.
In more detail, some treatments for genital psoriasis include the following:
Share on PinterestA doctor may inject biologics to treat moderate to severe psoriasis.
These disease-modifying therapies (DMT) are systemic medications that have an effect across the whole body.
They work to reduce the autoimmune response and could prove to be a key player in current research to develop a full cure.
Doctors administer biologics via infusion or injection.
For genital psoriasis, biologics are not a first-line treatment. However, they can be helpful for people who have genital psoriasis alongside other symptoms or those whose symptoms do not respond to other treatments.
Doctors tend to prescribe low-strength corticosteroids to soothe the symptoms of genital psoriasis. Overusing topical corticosteroids, however, may lead to permanently thin skin and stretch marks.
Using moisturizers available over the counter or online can help keep the area moisturized.
Vitamin D creams and ointments
These types of ointment are the most beneficial. Choosing moisturizers that contain fragrances and perfumes might cause irritation. A range of vitamin D creams is available for purchase online.
In special circumstances, UV light may help treat genital psoriasis. However, the dosage should be lower than what a person would use for a type of psoriasis that produces symptoms elsewhere on the body. This is because overuse can burn the delicate skin of the genitals.
Here, learn more about treating psoriasis with light therapy.
These cover the skin with a protective layer and prevent water loss. Emollients are available for purchase over the counter or online.
Tacrolimus and pimecrolimus can help treat genital psoriasis without thinning the skin. The Food and Drug Administration (FDA) have only approved these for use in eczema. However, they can also help with the symptoms of psoriasis.
Tacrolimus and pimecrolimus can, however, cause an uncomfortable burning sensation and reactivate sexually transmitted infections (STIs) such as herpes or viral warts.
In some cases, doctors might prescribe oral medication. However, genital psoriasis medications can cause some adverse side effects, including:
How can I treat genital psoriasis?
Genital psoriasis can be treated successfully: You apply most treatments for genital psoriasis directly to the psoriasis. If you have psoriasis on or around your genitals, you have genital psoriasis. Many people who have psoriasis will have a flare in this area. Even children get genital psoriasis. As embarrassing as this may feel, it is important to tell your dermatologist if you have psoriasis on (or around) your genitals. The right treatment can help:
Get rid of the itch, pain, and burning
Clear (or nearly clear) the psoriasis
If you are already treating psoriasis, it’s still important to tell your dermatologist about genital psoriasis. The skin in this area is thin and sensitive, so you’ll likely need a different treatment plan—and possibly different medicine.
What treatment is available for genital psoriasis?
A treatment plan may include:
Mild corticosteroid (with or without calcitriol ointment)
Medium-strength or potent corticosteroid (used for a short time)
Mild coal tar (use this only if a doctor recommends it)
Pimecrolimus cream or tacrolimus ointment
Stronger medicine such as cyclosporine, methotrexate, or a biologic
If you follow the treatment plan and it fails to work, tell your dermatologist. No one treatment works for everyone. You may need different treatment to get relief.
8 ways to avoid irritating genital psoriasis
To get the best results from treatment and avoid flares, you want to avoid irritating genital psoriasis. The following can help you do just that:
When treating genital psoriasis, use the treatment that your dermatologist prescribed for this area. Psoriasis treatment that you’re using on another part of your body can be harmful in the genital area. Tazarotene can irritate the area, making genital psoriasis worse. Any type of phototherapy (UVB, PUVA, or laser treatments) can increase your risk of developing genital cancer. Strong coal tar therapy may also increase the risk of genital cancer.
Tell your dermatologist if the treatment irritates any skin in your genital area.
Use a mild, fragrance-free cleanser. When bathing, you want to avoid deodorant or antibacterial soaps and body washes. These can irritate the delicate skin, causing genital psoriasis to flare.
Moisturize. Gently applying a fragrance-free moisturizer to the psoriasis after bathing and when the area feels dry can reduce chaffing and irritation.
Use quality toilet paper. This can help reduce irritation.
Avoid getting urine or feces on genital psoriasis. These can cause psoriasis to flare.
Wear loose-fitting underwear and clothing. Tight-fitting clothing can cause friction, which can worsen genital psoriasis.
Get plenty of fiber in your diet. Eating a high-fiber diet or taking a fiber supplement will ease bowel movements.
How to be intimate when you have genital psoriasis
If you have genital psoriasis, you can still be intimate. Following this advice can help reduce irritation:
When the skin on or around your genitals is raw, postpone sex.
Before sex, gently cleanse the area. Be sure to use a mild, fragrance-free cleanser. Cleansing will also help prevent psoriasis medication from rubbing onto your partner.
Men: Use a lubricated condom. Whether a man or woman has genital psoriasis, this lessens the risk of irritating the inflamed area.
After sex, gently wash the area. This helps reduce irritation. If you are using medicine, apply it.
Psoriasis is not contagious
If you have sex with someone who has psoriasis, you will not get psoriasis. Psoriasis is not contagious. It’s not a sexually transmitted disease.
Bergstrom, KG, Kimball AB. (2011) 100 questions & answers about psoriasis. Sudbury, Mass: Jones and Bartlett.
Meeuwis KA, de Hullu JA, et al. “Genital psoriasis awareness program: Physical and psychological care for patients with genital psoriasis.” Acta Derm Venereol. 2015 Feb;95(2):211-6.
Ryan C, Sadlier M, et al. “Genital psoriasis is associated with significant impairment in quality of life and sexual functioning.” J Am Acad Dermatol. 2015 Jun;72(6):978-83.
Turner J. “Inverse psoriasis.” National Psoriasis Foundation webinar, presented September 16, 2015.
All content solely developed by the American Academy of Dermatology
Supported in part by Novartis.
What Does Inverse Psoriasis Look Like?
There are several different treatment methods available for inverse psoriasis:
Topical creams, which are types of medication that you rub into your skin, are the first-line treatment method for inverse psoriasis.
The goal of treatment is to reduce inflammation and discomfort in these sensitive areas. Because the skin folds are so sensitive, medications must be used carefully.
Steroid creams can successfully reduce inflammation, but can also cause the skin to become thinner and more sensitive. If you’re prescribed a topical treatment, your doctor will monitor your progress and adjust the dosage if there are signs of skin thinning.
Topical medicines are usually used in the morning after you shower and once again before bedtime.
Alternatives to topical steroids are topical calcineurin inhibitors, tacrolimus, and pimecrolimus, which will stop the body’s immune system from producing substances that may cause skin disease.
Infected inverse psoriasis treatment
Because inverse psoriasis is prone to yeast and fungal infections, your doctor may dilute topical steroids and add anti-yeast and anti-fungal agents.
Phototherapy is a treatment option for people with moderate to severe inverse psoriasis. Phototherapy is the medical term for light therapy.
A form of ultraviolet light called UVB rays can effectively slow the growth of skin cells in some people with psoriasis.
Treatment with phototherapy involves using a light box that produces artificial UVB rays for a specified amount of time each session.
With phototherapy, your psoriasis might temporarily get worse before it gets better. Let your doctor know of any concerns about your rashes during light therapy treatment.
If your inverse psoriasis isn’t getting better with topical medications and phototherapy, your doctor might prescribe systemic drugs. These are medications taken either by mouth or injection.
One type of systemic drug is a biologic — a type of medication that changes the way your immune system works. Biologics use proteins to block the response of your immune system so it won’t attack your body as much.
If biologics are used as a treatment, your doctor will give you an injection or intravenous infusion of biologic drugs on a regular schedule. You might also continue with phototherapy or topical treatments at the same time.
Other systemic drugs that may be used are methotrexate or cyclosporine (Sandimmune), which moderate the immune system to decrease the action of certain skin cells.
Sometimes “not feeling well” seems worse than being “sick in bed.” When you have a mild cold, you still have to function in your job and home life. When you have the flu, however, you take days off and rest.
Inverse psoriasis is the “not feeling well” of psoriasis.
It’s not so bad that you have to stop living your regular life, but it’s really uncomfortable. Most of the time, you can hide your skin rash, but you never stop feeling it. You have irritated, itchy, and sometimes infected skin that never seems to let you forget your condition.
Fortunately, there’s a way to treat inverse psoriasis.
Once you figure out what triggers this condition for you, you’ll be able to make changes to soothe your skin and begin an inverse psoriasis treatment to help you keep it under control.
What Is Inverse Psoriasis?
Inverse psoriasis is psoriasis in the body folds. It can appear in the armpits, groin, genital area, behind the knees, or underneath the breasts. When psoriasis affects a crease in the skin, it’s considered inverse psoriasis.
Inverse psoriasis is often found in combination with other forms of psoriasis. Plaque psoriasis, the most common type, causes red, raised patches of skin, often covered with a white, plaque-like scale. These patches appear primarily on the knees, elbows, and scalp.
Think of inverse psoriasis as its opposite. Unlike plaque psoriasis, there’s not a heavy scale that builds on these irritated patches of skin. Instead, areas affected by inverse psoriasis are moist. The lesions are often an irritated red color, but the skin is shiny and smooth (rather than dry and scaly).
Inverse psoriasis can be tricky to diagnose. To the untrained eye, it looks more like an allergic reaction or a fungal infection. Your dermatologist will know the difference. Areas of the skin affected by inverse psoriasis are often more susceptible to fungal infections or yeast, but the main problem is psoriasis.
What Causes Inverse Psoriasis?
Psoriasis comes from a combination of genetic and environmental factors, but the specific triggers of psoriasis vary for every individual. People often experience a flare of psoriasis when there is stress to the body — mental, emotional, or physical. The physical stress of getting ill or experiencing a car accident may trigger the symptoms. The emotional stress of divorce or family illness could be another cause. Even the mental stress of college, tests, or a high-stakes work deadline can trigger psoriasis flares.
For others, food affects their condition. There aren’t specific foods that trigger psoriasis for everyone — this is very person-dependent. For some people, gluten triggers a reaction. Others can eat as much gluten as they want and their psoriasis won’t be affected.
There are also genetic links to psoriasis. It’s not 100% hereditary — just because your parents have it, doesn’t mean you’ll get it. However, it does tend to run in families.
Typically, it’s a combination of these factors that causes psoriasis to appear. If you get it, you’re likely genetically predisposed to psoriasis and experiencing a stressor (emotional, physical, mental, or food-related) that triggered a reaction.
For inverse psoriasis specifically, friction and heat are also triggers. Warmer months are especially bad for those with inverse psoriasis. People often notice lesions appear after times of high activity. For example, if you walk around Six Flags or Disney World for the day and later notice lesions in the groin or armpit, these were likely induced by heat and friction.
Inverse Psoriasis Treatment
Psoriasis is a chronic condition, but we have many treatment options that make it manageable.
For psoriasis, we always start treatment with a topical steroid. For inverse psoriasis, we use a mild steroid. Resist the temptation to use a steroid that was prescribed for another area of the body on your inverse psoriasis.
Unlike plaque psoriasis treatments, we’re not trying to penetrate a heavy scale with the medication. Instead, we’re dealing with moist skin that folds. As the skin rests against itself, it creates an occlusion effect which allows the medication to better penetrate the skin. If you use a steroid that’s too strong, you increase your risk of side effects such as thinning skin and stretch marks. To make sure you’re using the appropriate class of steroids, only use medications prescribed by the dermatologist for your inverse psoriasis treatment.
A topical steroid may be all you need to clear up your condition. If there’s little reoccurrence, you can just use as needed.
However, many patients need other non-steroidal treatments to keep inverse psoriasis under control. Often, we recommend Vitamin B Analog in addition to anti-fungal treatments. The areas affected by inverse psoriasis are dark, warm, and moist — which makes them a breeding ground for fungus. The fungus isn’t the source of the problem, but it makes the irritation and discomfort worse.
We also recommend applying a barrier ointment to affected areas. A product like Vaseline can be beneficial as it protects the skin against sweat and moisture. If you know you’ll be walking and creating friction in the areas of irritation, apply Vaseline to help the skin glide easier.
To find the best inverse psoriasis treatment for you, visit your dermatologist. They’ll be able to evaluate the severity of your condition and help you find the right combination of prescription and non-prescription medications for managing your inverse psoriasis.
With any type of psoriasis, make sure to visit your primary care doctor regularly. Psoriasis increases your risk of cardiovascular disease and joint problems. It’s important to stay on track with annual physicals to manage the risks involved. Your dermatologist can help you treat the skin irritations, while your primary care doctor can help you manage other related health concerns.
Inverse psoriasis requires regular attention and treatment, but it doesn’t have to cause constant discomfort. Don’t let inverse psoriasis make your everyday life uncomfortable. Call your dermatologist today, and they’ll help you find a treatment plan that works for you.
Mary Gurney, PA-C is a board-certified physician assistant in Denton and Frisco, TX. An active member of the Texas Academy of Physician Assistants and the Society of Dermatology Physician Assistants, Mary has a passion for medical and cosmetic dermatology and has practiced medicine for over 10 years in the DFW area. In her spare time, she enjoys watching movies, reading, hiking, checking out new restaurants in town, and spending time with her family.
Learn more about Mary Gurney.
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Scientific evidence shows that involvement of the genital skin occurs in 29–40% of patients with psoriasis . When there is inverse psoriasis, the genital area is usually involved in up to 79% of the patients . In dermatological consults for chronic symptomatic vulvar disorders, 2% of the cases are caused by psoriasis . Articles that analyzed non-neoplastic biopsies of vulva and vagina reported that 1.8–6.9% of the samples were histologically diagnosed as vulvar psoriasis . In children, vulvar psoriasis was the third most common cutaneous condition among prepubertal girls (9.5–17% of cases) . In males, genital psoriasis of the penis was diagnosed in 3% of patients with alterations of penile skin and genital skin folds . The etiology of inverse and genital psoriasis is still unknown and further studies are needed in order to clarify these diseases . However, as treatment for psoriasis vulgaris is also effective for genital psoriasis, it seems to have a pathophysiology similar to plaque psoriasis in other skins zones. The pathophysiology involves an alteration in the activation of CD4+ and CD8+ T-cells and an anomalous proliferation and differentiation of keratinocytes. It is still not understood as to what causes the disease to commence in this particular zone; the anomalous proliferation and differentiation of keratinocytes suggests that maybe the Koebner phenomenon of constant local mechanical and chemical irritation of flexion folds possibly perpetuates the process .
Inverse psoriasis in genital skin folds usually presents itself as erythematous, irregular, well-demarcated, thin, and often symmetrical plaques in the vulva and vagina, with poor or non-desquamation because of the local conditions, as discussed earlier and lacks the typical scaling of plaque psoriasis in other skin zones. However, minimal scaling can be seen on the more keratinized regions of the genital skin . The mucosa of the vagina can also be compromised as part of genital psoriasis, showing exudative and bright erythematous plaques, this compromise is less frequently diagnosed in women than in men . Lesions may also have fissures, maceration, and rhagades, and may be accompanied with pruritus, pain, or burning sensation, causing irritation and scratching, producing more plaques through the Koebner phenomenon and local lichenification; therefore, perpetuating the process. Other conditions may also cause irritation, such as sexual intercourse, urine, feces, underwear, clothes, and local infections . Genital psoriasis usually does not produce scarring. However, one case report of two patients described atrophic scarring of the labia minora, mimicking the scarring caused by genital lichen sclerosus . Another condition rarely seen is genital compromise with pustular psoriasis as part of a localized or generalized pustular process, but this complication has only been reported in men . Genital psoriasis can affect not only prepubertal girls, but also small children presenting localized or disseminated psoriatic eruptions in the napkin and genital area . Reports showed that 13% of children with psoriasis had psoriatic napkin eruptions with dissemination, whereas 4% had a localized psoriatic napkin eruption , with anogenital psoriasis occurring four-times more often in children over 2 years old than in children under 2 years of age .
Diagnosis is based on clinical background, symptoms, clinical signs, and the appearance of skin lesions in the genital area or elsewhere in the body . However, in cases where genital lesions are the only clinical finding, skin biopsy might be an option, showing the same classical histopathological characteristics of non-genital plaque psoriasis, such as Kogoj’s and Munro-Sabouraud’s collections of neutrophils, thickening of the Malpighian layer, hypogranulosis, hyperkeratosis, parakeratosis, and elongation of the papillae , but with the slight difference that this findings may be less evident in vulvar and penile psoriatic lesions .
There are numerous therapeutic options for treating psoriasis, which is a therapeutic challenge when it is limited to intertriginous areas such as genital skin flexion folds. So far, there are few evidence-based studies regarding the treatment of inverse psoriasis involving genital flexion folds, and data related to efficacy and safety are extremely limited and only supported by expert opinion (level of evidence 5 and recommendation class D) . In fact, only six casuistic reports and one open-label study have described the effects of therapies used , and 24 articles, selected by the only systematic literature review available, reflected the opinion of experts on the preferred treatment for genital psoriasis .
Evidence-based recommendations for genital psoriasis indicate the use of short-term topical low-to-medium power corticoids as a first-line treatment option, which can be combined with vitamin D analogs or mild tar preparations . Experts advise the intermittent, short-term use of moderate-to-potent corticosteroids followed by a subsequent gradual shift towards a weaker corticosteroid in cases where weak corticosteroids seem insufficiently potent to induce a response; these treatments should always be monitored for possible local atrophic effects . Mild topical coal-tar preparations are the second most advised topical therapy in adults and the first choice for children with napkin plaque psoriasis , and are used as an individual topical therapy or combined/alternated therapy with topical steroids . It should be noted that secondary effects have been reported, such as irritation or folliculitis . The use of tar preparations with a steroid preparation has been recommended to reduce irritation . In children, it can also be used mixed with zinc oxide . Topical treatment of vitamin D analogs (such as calcipotriol) has also shown benefits either alone as monotherapy or combined with steroid preparations (to reduce the irritation that these analogs cause), especially in male patients . The use of topical immunomodulator agents, such as tacrolimus or 1% pimecrolimus cream, have shown benefits for long-term therapies , and should be regarded as third-line treatment options , but patients should be monitored periodically for possible complications, such as local irritation, stinging, irritant or allergic contact dermatitis, candidiasis, and/or (re)activation of viral skin infections . Topical cyclosporine has also shown beneficial effects when used in genital psoriasis of the glans, penis, and prepuce . If concurrent bacterial or fungal infections are present, they should be treated with topical antibiotics or antifungal drugs, and local irritation should be reduced with mild emollients in order to eliminate the possible Koebner effect . If vulvar plaques are resistant to treatment, a biopsy should be carried out to rule out malignancy .
Systemic therapies (methotrexate, cyclosporine, oral retinoids, or biological drugs) are used for severe or extensive psoriasis, or when there is a significant negative impact on quality of life , but they are not used as common practice for isolated genital psoriasis . Local treatment with topical dithranol (anthralin) and tazarotene should be avoided in the genital area . Laser therapies (excimer, continuous carbon dioxide, erbium, pulsed dye laser) and UV phototherapy are commonly used for localized skin plaque psoriasis , except for YAG (yttrium–aluminum–garnet) laser, which has been shown not to improve localized plaque psoriasis . However, these treatments are not recommended for genital psoriasis. Moreover, it has been suggested that these modalities should be avoided in inverse psoriasis with compromised genital skin folds .
Nonstandard and off-label therapies for psoriasis should be chosen when there is resistance to conventional therapies, when there are multiple side effects, in unusual presentations, or in cases with specific comorbidities . One of these therapies is dapsone, a sulfone initially used for the treatment of leprosy. Nowadays, its use has extended to other inflammatory dermatoses . It has antibiotic, anti-inflammatory, and immunomodulatory properties . MacMillan and Champion first reported the use of dapsone as a treatment for psoriasis in an adult with treatment-resistant generalized pustular psoriasis . Since then it has been used in cases of pustular psoriasis, especially in children . Side effects are dose-dependent, hemolysis and methemoglobinemia being the most frequently reported, and more rarely reported agranulocytosis, hypersensitivity syndrome, and peripheral neuropathy . The recommended dosing of dapsone in childhood pustular psoriasis is 1 mg/kg daily, whereas in adults with dermatitis herpetiformis a starting dose of 50 mg daily is recommended, which can be increased, as tolerated, up to 300 mg daily or higher if necessary. The dosage should be reduced to a lower maintenance dose if possible . Dapsone has been chosen by physicians as a treatment option for genital psoriasis; this type of therapeutic regimen was first described in 2008 in a case report by Singh and Thappa . They used dapsone 100 mg daily in a male patient with pustular psoriasis of the penis, the lesions subsided completely after 4 weeks of treatment, similar to the results obtained in the present case. Regarding monitoring, it is recommended that complete blood cell and platelet counts are undertaken weekly for 4 weeks, monthly for 6 months, and then every 6 months, and liver function tests and total bilirubin are performed periodically .
In conclusion, genital psoriasis is a skin disease that causes great discomfort. It is important to include an examination of the genital region and to adopt this conduct in daily clinical practice. Thus far, research in this field is poor, making no discrimination between flexural and genital psoriasis, and is based on case series and expert opinion; therefore, recommendations for the treatment of genital psoriasis are empirical. Dapsone has been shown to be an effective and convenient alternative for the treatment of inverse psoriasis in genital skin folds, which can provide effective control of the disease. Further studies are required to determine the efficacy and safety of current therapies, and to decide whether this therapy should be considered in the management of this form of psoriasis when topical and other systemic agents are not effective.