context: Knowing which kind of psoriasis you have helps you and your doctor make a treatment plan. Most people have only one type at a time. Sometimes, after your symptoms go away, a new form of psoriasis will crop up in response to a trigger. In general, most types of psoriasis result from the same triggers: Stress Skin injury Medications Lithium Antimalarial drugs Inderal Quinidine Indomethacin Infection Other things that may trigger psoriasis include: Allergies Diet Weather Here's how you can spot the 7 types of psoriasis and what you can do to treat them. This is the most common type. About 8 in 10 people with psoriasis have this kind. You may hear your doctor call it "psoriasis vulgaris." Symptoms: Plaque psoriasis causes raised, inflamed, red skin covered with silvery, white scales. These patches may itch and burn. It can appear anywhere on your body, but it often pops up in these areas: Elbows Knees Scalp Lower back Treatments: Topical treatments: These go on your skin and are usually the first thing doctors try. Some have steroids; others don't. Prescription products slow skin cell growth and ease inflammation. Phototherapy: This treatment uses ultraviolet light. You'll get it at your doctor's office or at home with a phototherapy unit. Systemic medications: These prescription drugs work throughout your body. You'll get them if you have moderate to severe psoriasis that doesn't respond to other treatments. You could take them by mouth or get them as a shot or IV. This category includes drugs called biologics, which target specific parts of your immune system that play a role in the inflammatory process. This type often starts in children or young adults. It happens in less than 2% of cases. Guttate psoriasis causes small, pink-red spots on your skin. They often appear on your: Trunk Upper arms Thighs Scalp This type of psoriasis may go away within a few weeks, even without treatment. Some cases, though, are more stubborn and require treatment. This type usually found in these locations: Armpits Groin Under the breasts Skin folds around the genitals and buttocks Symptoms include: Patches of skin that are bright red, smooth, and shiny, but don't have scales Getting worse with sweating and rubbing Common triggers are: Friction Sweating Fungal infections This kind of psoriasis is uncommon and mostly appears in adults. It causes pus-filled bumps (pustules) surrounded by red skin. These may look infectious, but are not. This type may show up on one area of your body, such as the hands and feet. Sometimes it covers most of your body, which is called "generalized" pustular psoriasis. When this happens, it can be very serious, so get medical attention right away. Symptoms include: Fever Chills Nausea Fast heart rate Muscle weakness Triggers include: Topical medicine (ointments you put on your skin) or systemic medicine (drugs that treat your whole body), especially steroids Suddenly stopping systemic drugs or strong topical steroids that you used over a large area of your body Getting too much ultraviolet ( UV) light without using sunscreen Pregnancy Infection Stress Exposure to certain chemicals This type is the least common, but it's very serious. It affects most of your body and causes widespread, fiery skin that appears to be burned. Other symptoms include: Severe itching, burning, or peeling A faster heart rate Changes in body temperature If you have these symptoms, see your doctor right away. You may need to get treated in a hospital. This type of psoriasis can cause severe illness from protein and fluid loss. You may also get an infection, pneumonia, or congestive heart failure. Triggers include: Suddenly stopping your systemic psoriasis treatment An allergic drug reaction Severe sunburn Infection Medications such as lithium, antimalarial drugs, cortisone, or strong coal tar products Erythrodermic psoriasis may also happen if your psoriasis is hard to control. Up to half of those with psoriasis have nail changes. Nail psoriasis is even more common in people who have psoriatic arthritis, which affects your joints. Symptoms: Pitting of your nails Tender, painful nails Separation of the nail from the bed Color changes (yellow-brown) Chalk-like material under your nails You're also more likely to also have a fungal infection. Psoriatic arthritis is a condition where you have both psoriasis and arthritis (joint inflammation). In 70% of cases, people have psoriasis for about 10 years before getting psoriatic arthritis. About 90% of people with it also have nail changes. Symptoms: Painful, stiff joints that are worse in the morning and after rest Sausage-like swelling of the fingers and toes Warm joints that may be discolored