What triggers psoriasis?
Triggering factors are events or conditions that cause psoriasis to flare up or worsen. If you are genetically predisposed to developing psoriasis, you may find that certain triggers activate the condition, although it is important to note that, in most cases, the specific triggers cannot be identified.
Streptococcal infection: This infection is a common cause of sore throats and tonsillitis. It can be pinpointed as a specific trigger in some people with psoriasis, particularly in children and young adults.
Strep throat can lead to guttate psoriasis in children and young adults. Anyone with psoriasis who gets strep throat should be treated promptly with antibiotics to prevent a flare-up of psoriasis. HIV infection can cause psoriasis to flare up or to appear for the first time. Severe forms of psoriasis, such as inverse psoriasis, become more common as HIV infection progresses and the immune system becomes weaker.
Sun exposure: Lengthy exposure to a dry climate with low relative humidity can make psoriasis worse. For many people, sun exposure during the summer helps to clear psoriasis. However, people who are sun-sensitive find that psoriasis flares up when skin is exposed to the sun. The sun's UV rays actually help the vast majority of people with psoriasis. However, for a very small minority (less than 5%), sunlight can aggravate the condition. Sunburn may also cause psoriasis to flare up.
Drug reactions: Certain medications may make psoriasis worse. These include lithium (prescribed to treat bipolar disorder), beta blockers (prescribed for heart problems), anti-malarial drugs, and nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (available by prescription or over the counter for pain relief). NSAIDs are often used to treat psoriatic arthritis. In such cases, the benefits and risks of treatment need to be carefully assessed. Flare-ups of psoriasis caused by NSAIDs usually respond to treatment. Abuse of alcohol, on the other hand, can make psoriasis treatment ineffective.
Hormonal factors: With women, hormonal factors can vary greatly. The effect of pregnancy on psoriasis is very unpredictable. Peak onset also tends to be when the periods start during puberty.
Psychological factors: Some people find that stress acts as a trigger. However this can work both ways. A person may find that having psoriasis causes them to get stressed. Severe emotional stress may play a role in the appearance of psoriasis or in flare-ups of the disease. However, the impact of stress can be difficult to assess. Techniques to reduce stress can be helpful if flare-ups of psoriasis follow a pattern and stress factors can be recognized as part of that pattern.
Skin trauma: Psoriasis may develop if the skin is injured. This is known as the Koebner phenomenon. It most commonly appears as a line in an operation scar or in a scratch. It may also appear in the spots of chickenpox. This type of psoriasis often heals on its own.