Psoriasis Triggers

The cause of psoriasis isn’t fully known, but it's thought to be related to the immune system and its interaction with the environment in people who have the genetic susceptibility. More specifically, one key cell is a type of white blood cell called a T lymphocyte or T cell. Normally, T cells travel throughout the body to detect and fight off foreign substances, such as viruses or bacteria. If you have psoriasis, however, the T cells attack healthy skin cells by mistake, as if to heal a wound or to fight an infection.

Overactive T cells trigger other immune responses. The effects include dilation of blood vessels in the skin around the plaques and an increase in other white blood cells that can enter the outer layer of skin. These changes result in an increased production of both healthy skin cells and more T cells and other white blood cells. This causes an ongoing cycle in which new skin cells move to the outermost layer of skin too quickly — in days rather than weeks. Dead skin and white blood cells can't slough off quickly enough and build up in thick, scaly patches on the skin's surface. This usually doesn't stop unless treatment interrupts the cycle.

Just what causes T cells to malfunction in people with psoriasis isn't entirely clear, although researchers think genetic and environmental factors both play a role.

Psoriasis triggers
 

Psoriasis typically starts or worsens because of a trigger that you may be able to identify and avoid. Factors that may trigger psoriasis include:

• Infections, such as strep throat or thrush
• Injury to the skin, such as a cut or scrape, bug bite, or a severe sunburn
• Stress
• Cold weather
• Smoking
• Heavy alcohol consumption
• Certain medications — including lithium, which is prescribed for bipolar disorder; high blood pressure medications such as beta blockers; antimalarial drugs; and iodides.

Stress

Studies have shown stress can worsen psoriasis. When you're stressed, your body reacts. And while stress is known to make psoriasis worse, psoriasis can make you more stressed out. 

Breathe deep and count to 10. Take a relaxing soak in the tub. Call up a friend to vent. Meditate. Focus on the positive and incorporate relaxation techniques into your daily routine. All are ways to bust stress and perhaps help keep psoriasis flares at bay.

 

Allergies

Are psoriasis and allergies linked? The immune system appears to play a key role in both.
Researchers have found that people with psoriasis are more likely to have a greater number of inflammatory mast cells (see left) -- the kind that trigger allergic reactions, such as swelling and itching -- than people without it. Although psoriasis may be a reaction of the immune system, it is not proven to be an allergic reaction. Studies have found no link between allergens and psoriasis. 

Alcohol

Many lifestyle choices can affect psoriasis. Drinking alcohol has been associated with psoriasis and its severity. While more research is needed, it's believed that heavy drinking can trigger flares in some people. Doctors say avoid alcohol altogether to help prevent psoriasis flare-ups.
Another reason to put down your drink? Some psoriasis medications and drinking don't mix.
Instead, try a nonalcoholic thirst-quencher like iced tea. Or walk around the block to unwind. Getting exercise and up to 20 minutes of sunlight a day can soothe psoriasis.

Cold or Dry Weather

Winter can be especially hard on those who live with psoriasis. Cold, dry weather can worsen psoriasis, while warm, sunny climates may help alleviate it.
Keep your skin well moisturized. Use thick, creamy lotions after showers and baths and throughout the day. Look for lotions and soaps that are fragrance-free and designed for sensitive skin to help reduce irritation.
You can also use a humidifier in your home during dry months to help keep your skin moist. Keeping the skin moist can help reduce itching and tenderness.

Tattoos

Tattoos can look cool, but to psoriatic skin the tattooing process can be a nightmare. Repeatedly piercing the skin and injecting it with dyes is a major trauma. Trauma to the skin can cause new lesions to appear, often 10 to 14 days later.
Tattoos can also lead to infection -- another psoriasis trigger.
Treat your skin with care. Avoid tattoos and acupuncture, and talk with your doctor about shots.

Medications

Some drugs used to treat high blood pressure, heart disease, arthritis, and psychiatric disorders can trigger psoriasis.
ACE inhibitors, beta-blockers, and lithium are common offenders that can cause psoriasis flare-ups as well as malaria drugs, such as Plaquenil and hydroxychloroquine, and NSAIDs. Oral steroids such as prednisone work to control flares but may cause a worsening of the condition after coming off long-term use.
Talk to your doctor if your medication is worsening your psoriasis.

Infections

Common infections are doubly difficult for people with psoriasis. Yeast infections, thrush, strep throat, respiratory infections, and staph infections are all known psoriasis triggers.
The good news? Once you treat the infection, your psoriasis flare may also calm down.
 

Cuts and Bruises

Slice your hand in the kitchen or scrape a knee and -- pow! -- new lesions may appear where you were injured. This is called Koebner's phenomenon.
Avoid skin injury and trauma when you can. 
Wear gloves while working in the garden. Prevent bug bites and sunburn. And use care when trimming nails and shaving.

Smoking

Research shows smoking is directly linked to the severity of your psoriasis. The more you smoke, the worse your flare-ups, with outbreaks most often appearing on the hands and feet. 
Kicking the habit may reduce the number of psoriasis flares and, for some, end them.  
You don't have to take on the challenge alone. Ask your doctor about ways to smooth the transition to becoming smoke-free.

Hormones

Psoriasis can start at any age in both men and women. But it seems to peak in people between the ages of 20 and 30 as well as those between the ages of 50 and 60. Both puberty and menopause also seem to trigger psoriasis patches. Hormones are often thought to be the link.
Interestingly, one study found that high levels of estrogen during pregnancy seemed to improve psoriasis in some women.

Types of psoriasis

Many forms of psoriasis

Psoriasis occurs when the life cycle of skin cells speeds up, resulting in a rapid buildup of rough, dead skin cells. These skin cells accumulate, forming thick silvery scales and itchy, dry, red patches that are sometimes painful. In some cases, pus-filled blisters appear.
Psoriasis patches can range from a few spots of dandruff-like scaling to major eruptions that cover large areas.
Though psoriasis signs and symptoms vary from person to person, psoriasis types are typically identified by their hallmark appearance. Here's a look at psoriasis pictures, showing classic signs and symptoms. 

Plaque psoriasis

Plaque psoriasis, the most common form of psoriasis, causes dry, raised, red skin lesions (plaques) covered with silvery scales. The plaques itch or may be painful and can occur anywhere on your body. You may have just a few plaques or many, and in severe cases, the skin around your joints may crack and bleed.
Lifestyle measures, such as using a nonprescription cortisone cream and exposing skin to small amounts of natural sunlight, may improve mild cases. Moderate or severe cases may require light therapy, prescription steroid creams, oral medications or a combination of these. 

Scalp psoriasis

Scalp psoriasis appears as red, itchy areas with silvery-white scales. You may notice flakes of dead skin in your hair or on your shoulders, especially after scratching your scalp. The scaly patches, which may bleed when removed, may extend beyond your hairline.
Treatment for scalp psoriasis includes medicated shampoo, steroid foam or lotion, and oral medications. 

Nail psoriasis

Psoriasis can affect fingernails and toenails, causing pitting, abnormal nail growth and discoloration. Psoriatic nails may become loose and separate from the nail bed (onycholysis). Severe cases may cause the nail to crumble.
Nail psoriasis often accompanies another type of psoriasis, such as plaque psoriasis. Treatment options include oral medications and light therapy. 

Guttate psoriasis

Guttate psoriasis is usually triggered by a bacterial infection such as strep throat. It's marked by small, water-drop-shaped sores on your trunk, arms, legs and scalp. The sores are covered by a fine scale and aren't as thick as typical plaques are. You may have a single outbreak that goes away on its own, or you may have repeated episodes.
Guttate psoriasis typically responds to treatment, which includes light therapy, prescription steroid creams and oral medications. It may also improve with treatment of the underlying cause or infection, if identified. 

Inverse psoriasis

Inverse psoriasis causes smooth patches of red, inflamed skin primarily in the armpits, groin, under the breasts and around the genitals. Inverse psoriasis is more common in obese people and is worsened by friction and sweating.
Treatment of inverse psoriasis may include taking a prescription oral medication. 

Pustular psoriasis

Pustular psoriasis can occur in widespread patches or in smaller areas on your hands, fingertips or feet, as shown here. It can develop quickly, with pus-filled blisters appearing just hours after your skin becomes red and tender. The blisters dry within a day or two but may reappear every few days or weeks. The reaction can result from medications, an infection, severe irritation or light sensitivity.
Small patches of pustular psoriasis may be treated with a steroid cream. Larger patches usually require prescription oral medication, elimination of the underlying cause, if possible, and other topical and systemic therapies. Light therapy may be useful once the blisters resolve and the skin is less irritated. 

Erythrodermic psoriasis

Erythrodermic psoriasis, the least common type of psoriasis, can cover your entire body with a red, peeling rash that can itch or burn intensely. It may be triggered by corticosteroids or other medications, severe sunburn or sensitivity to light during phototherapy treatment, or by another type of psoriasis that's poorly controlled.
Treatment of erythrodermic psoriasis usually requires prescription oral medication, medicated wet dressings and topical steroids. Combination therapies and hospitalization may be necessary for severe cases.