Psoriasis: symptoms, types, triggers and treatment options, a review

Psoriasis is a long-term skin condition that affects people of many ages. It causes patches of thick, scaly skin and can also affect the nails and joints. This article explains the condition, using information from the NHS, MedlinePlus and the US National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS).

1. Introduction

The NHS describes psoriasis as a common, long-term skin condition causing itchy, painful, dry, flaky patches, and states that it is not contagious ^[1]. MedlinePlus says it usually appears in adults, can last a lifetime and has symptoms that come and go ^[2]. NIAMS explains that it is a chronic disease in which the immune system is overactive, so skin cells multiply too quickly ^[3]. Normally skin cells rise to the surface over about a month, but in psoriasis this can happen in days ^[2].

2. Signs and symptoms

On white skin, patches are usually pink or red with silvery-white scales. On brown or black skin, patches may look grey and can leave dark marks after they clear ^[1]. Patches are often 1 to 2 centimetres across, and some people have only a few while others have many small scaly spots ^[1].

Common sites are the scalp, behind the ears, elbows, knees, lower back, chest and lower legs. Psoriasis can also affect skin folds, the palms and soles, and the nails, which may become pitted, thick or ridged ^{[1, 3]}. Skin can be itchy, sore, cracked or bleeding, and sleep can suffer ^[3]. It can start at any age, often between 15 and 25 or between 50 and 60, and symptoms alternate between flare-ups and better periods ^[1]. NIAMS says it is more common in adults than in children and affects men and women equally ^[3].

3. Types of psoriasis

NIAMS lists these main types ^[3]:

• Plaque: the most common type, with raised red patches and silvery-white scales.
• Guttate: small red dots, often in children or young adults and sometimes triggered by a throat infection.
• Pustular: pus-filled bumps surrounded by red skin, usually on the hands and feet.
• Inverse: smooth red patches in skin folds such as under the breasts or in the groin.
• Erythrodermic: a rare but serious type with red, scaly skin over most of the body.

4. Causes and triggers

The exact cause is not fully understood. It involves the immune system, genes and the environment, and many people have a relative with psoriasis ^{[1, 3]}. Possible triggers include ^{[1, 3]}:

• Stress
• Alcohol and smoking
• Being overweight
• Infections, such as a streptococcal throat infection
• Skin injuries such as cuts or grazes
• Some medicines, including certain medicines for heart disease, malaria or mental health conditions
• Sunlight, in some people (severe sunburn is a trigger for the erythrodermic type)

Triggers differ for each person, so keeping a note of what comes before flare-ups can help you discuss them with your doctor.

5. Diagnosis

Psoriasis can look like other skin diseases, which can make it hard to diagnose. MedlinePlus says a doctor may examine a small skin sample under a microscope ^[2]. A dermatologist, a doctor who specialises in skin, may be involved.

6. Treatment and management

Treatment depends on the type, severity and location ^{[1, 3]}. The NHS lists these groups ^[1]:

• Moisturisers (emollients) for the skin and for washing
• Vitamin D based creams, lotions and ointments
• Steroid creams or ointments applied to the skin
• Other skin treatments such as coal tar
• Light therapy and other medicines for more severe cases, which NIAMS says may be tablets or injections for moderate to severe disease ^[3]

Combinations are common, and a doctor can refer you to a dermatologist ^[1]. Mental health support is available if psoriasis affects your wellbeing ^[1].

Everyday habits help. The NHS suggests avoiding known triggers, eating a balanced diet, exercising, managing stress, limiting alcohol and stopping smoking ^[1]. As with eczema, do not share moisturisers and avoid naked flames when clothes or bedding have emollient on them ^[1].

7. Associated conditions and special groups

Some people develop psoriatic arthritis, a joint condition. NIAMS lists joint stiffness, swelling or pain and neck, back or Achilles heel pain as signs, and says seeing a doctor promptly matters because untreated psoriatic arthritis can cause permanent damage ^[3]. NIAMS also reports links with heart disease, diabetes, metabolic syndrome, obesity, inflammatory bowel disease and low mood or anxiety ^[3]. The NHS advises regular check-ups and reporting any new symptoms to a doctor ^[1].

In pregnancy, treatment may need to change because some medicines can be harmful, and pregnancy can also worsen symptoms. The NHS advises speaking to a doctor or pharmacist ^[1].

8. When to see a doctor

See a doctor if you have symptoms of psoriasis, if treatment is not working or is causing side effects, or if you have recurring joint pain, stiffness or swelling ^[1].

Seek emergency care if the skin quickly turns red with white pus-filled bumps that merge, if you have yellow-brown pus-filled patches on the feet, or red scaly pus-filled bumps at the fingertips or toes, especially with a fast heartbeat, high temperature or feeling hot, cold or shivery ^[1]. The NHS advises not driving yourself and taking your medicines with you.

In an emergency, call your local emergency number (112 in India, 911 in the United States).

9. Conclusion

Psoriasis is a long-term, non-contagious condition driven by the immune system. Many people keep it under control with a treatment plan, skin care, healthy habits and attention to triggers. Joint symptoms and rapidly changing skin need prompt medical review. Your doctor decides which treatment is right for you.