If your psoriasis is severe or other treatments haven't worked, you may be prescribed systemic treatments by a specialist. Systemic treatments are treatments that work throughout the entire body.
These medications can be very effective in treating psoriasis, but they all have potentially serious side effects. All the systemic treatments for psoriasis have benefits and risks. Before starting treatment, talk to your doctor about your treatment options and any risks associated with them.
There are two main types of systemic treatment, called non-biological (usually given as tablets or capsules) and biological (usually given as injections). These are described in more detail below.
Non-biological medications
Methotrexate
Methotrexate can help to control psoriasis by slowing down the production of skin cells and suppressing inflammation. It's usually taken once a week.
Methotrexate can cause nausea and may affect the production of blood cells. Long-term use can cause liver damage. People who have liver disease shouldn't take methotrexate, and you shouldn't drink alcohol when taking it.
Methotrexate can be very harmful to a developing baby, so it's important that women use contraception and don't become pregnant while they take this drug and for three months after they stop. Methotrexate can also affect the development of sperm cells, so men shouldn't father a child during treatment and for three weeks afterwards.
Ciclosporin
Ciclosporin is a medicine that suppresses your immune system (immunosuppressant). It was originally used to prevent transplant rejection, but has proved effective in treating all types of psoriasis. It's usually taken daily.
Ciclosporin increases your chances of kidney disease and high blood pressure, which will need to be monitored.
Acitretin
Acitretin is an oral retinoid that reduces the production of skin cells. It's used to treat severe psoriasis that hasn't responded to other non-biological systemic treatments. It's usually taken daily.
Acitretin has a wide range of side effects, including dryness and cracking of the lips, dryness of the nasal passages and, in rarer cases, hepatitis.
Acitretin can be very harmful to a developing baby, so it's important that women use contraception and don't become pregnant while they take this drug, and for two years after they stop taking it. However, it's safe for a man taking acitretin to father a baby.
Biological treatments
Biological treatments reduce inflammation by targeting overactive cells in the immune system. These treatments are usually used if you have severe psoriasis that hasn't responded to other treatments, or if you can't use other treatments.
Etanercept
Etanercept is injected twice a week and you'll be shown how to do this. If there's no improvement in your psoriasis after 12 weeks, the treatment will be stopped.
The main side effect of etanercept is a rash where the injection is given. However, as etanercept affects the whole immune system, there's a risk of serious side effects, including severe infection. If you had tuberculosis in the past, there's a risk it may return. You'll be monitored for side effects during your treatment.
Adalimumab
Adalimumab is injected once every two weeks and you'll be shown how to do this. If there's no improvement in your psoriasis after 16 weeks, the treatment will be stopped.
Adalimumab can be harmful to a developing baby, so it's important that women use contraception and don't become pregnant while they take this drug, and for five months after the treatment finishes.
The main side effects of adalimumab include headaches, a rash at the injection site and nausea. However, as adalimumab affects the whole immune system, there's a risk of serious side effects, including severe infections. You'll be monitored for side effects during your treatment.
Infliximab
Infliximab is given as a drip (infusion) into your vein at the hospital. You'll have three infusions in the first six weeks, then one infusion every eight weeks. If there's no improvement in your psoriasis after 10 weeks, the treatment will be stopped.
The main side effect of infliximab is a headache. However, as infliximab affects the whole immune system, there's a risk of serious side effects, including severe infections. You'll be monitored for side effects during your treatment.
Ustekinumab
Ustekinumab is injected at the beginning of treatment, then again four weeks later. After this, injections are every 12 weeks. If there's no improvement in your psoriasis after 16 weeks, the treatment will be stopped.
The main side effects of ustekinumab are a throat infection and a rash at the injection site. However, as ustekinumab affects the whole immune system, there's a risk of serious side effects, including severe infections. You'll be monitored for side effects during your treatment.
Newer drugs
Ixekizumab and secukinumab are fairly new biological treatments. They're recommended as possible treatments for severe psoriasis when this hasn't improved with other treatments, or when other treatments aren't suitable.
Want to know more?