Some chemotherapy medications, such as methotrexate and photochemotherapy, have been repurposed to treat psoriasis. To treat psoriasis, doctors will use lesser doses of these medications than they would for cancer.
Psoriasis is a debilitating inflammatory condition that can range from little raised skin patches to severe lesions that cover vast regions of the body. Psoriatic arthritis, which is caused by this condition, can cause painful joints.
For mild-to-moderate instances of psoriasis, the first-line therapy is to apply lotions or ointments to the afflicted region. Corticosteroids may be used as topical therapies. Vitamin D analogs and phototherapy are two more treatments. If the condition is mild to severe, injections or oral therapies will be required.
There is currently no cure for psoriasis. Treatment, on the other hand, can help patients with psoriasis control their symptoms and even go into remission. Medical personnel will discuss the various treatment choices as well as the potential adverse effects of the drugs given.
In this article, we look at how methotrexate and photochemotherapy can be used to treat psoriasis. We also look at side effects and other treatment options.
Photochemotherapy (PUVA) is a treatment that combines the use of psoralens, which are plant-derived or synthetic compounds, with UVA exposure. Psoralen makes the skin more light-sensitive. UVA light alone is not as effective as this combined therapy.
When psoriasis covers more than 20% of the body, which is considered a severe disease, doctors frequently employ PUVA as a therapy.
When other therapies have failed to eradicate psoriasis or when remission is short, healthcare practitioners may consider PUVA.
This therapy is divided into two parts by doctors: an initial cleaning phase and a maintenance phase. There will be two to three therapy sessions per week during the first phase, with a minimum of 48 hours between each session. Remission might take anywhere from 25 to 30 visits, depending on the severity of the condition.
Once the psoriasis has gone, a person will need to attend maintenance sessions. If the psoriasis flares again, patients may need to return to therapy.
According to studies, PUVA combo treatment is 80 percent effective in lowering psoriasis severity.
Possible PUVA side effects
While PUVA has the potential to be useful, it also has the potential to be dangerous.
People should not skip visits because this will reduce the effectiveness of the treatment. People must wear safety goggles during therapy since UVA exposure might induce cataracts. The drugs that a person is taking for various ailments should be kept up to date with their doctor.
The skin may seem somewhat flushed or darker following therapy, but other negative effects on the skin include:
- dark spots appearing
- mild burning or stinging
- blisters or a burn
Possible long-term side effects may include:
- early skin aging, including wrinkles, loose skin, or age spots
- increased risk of skin cancer
A person should not use PUVA if they:
- have skin cancer, or a medical condition that could make people more likely to develop skin cancer
- have a medical condition that could make people more sensitive to UV light, such as lupus
- are taking medication that increases sensitivity to UV light, including some skin creams
- have a heart or brain condition
- are pregnant, although PUVA will not cause a problem for future pregnancies once the person has finished treatment
Treating side effects of PUVA
PUVA has been linked to an increased risk of skin cancer. Doctors may examine a patient’s skin for symptoms of skin cancer while they are having PUVA.
People undergoing this treatment should avoid the following:
- using a sunbed during treatment
- going out into the sun without appropriate strong protection in the form of sunscreen and clothing
- exposing their skin to the sun on the day of treatment
If patients attending PUVA visits acquire dry, itchy skin, they should apply emollients such aqueous cream to relieve the irritation. Chemical compounds that enhance sensitivity to the sun, such as perfume, aftershave, and certain deodorants, should also be avoided.
Methotrexate is and has long been a standard first-line therapy for psoriasis. Doctors administer it at a lesser dose than they would for a cancer patient, coupled with folic acid, to lessen the drug’s negative effects.
According to a 2016 meta-analysis of methotrexate therapy for psoriasis, 45.2 percent of patients had a three-quarters reduction in the percentage afflicted area after 12–16 weeks.
Methotrexate can be taken as an injection or as a tablet. The suggested dosage should be discussed with a doctor or pharmacist.
A weekly dose of 10–25 milligrams (mg) is indicated for those with psoriasis. To obtain the best clinical response, the dose is progressively increased. Doctors recommend that consumers use no more than 25 mg each week.
The suggested starting dose is 7.5–10 mg per week, with clinicians having the option of increasing it to a maximum of 25 mg per week.
Each tablet has a dosage of 2.5 mg. Once a week, people normally take a single dose of tablets.
Possible side effects of methotrexate
People are unable to use methotrexate under the following circumstances:
- when trying for a baby, as it can cause fetal toxicity and fetal death
- during pregnancy
- when breastfeeding
- if a person previously experienced a severe reaction or anaphylaxis
- if a person regularly consumes large quantities of alcohol
- if a person has liver disease
- if a person has a weakened immune system
- if a person has certain blood conditions, such as anemia or leukopenia
In a 2016 meta-analysis, the adverse effects of methotrexate limited treatment in around 7% of cases.
Methotrexate can also create severe but rare reactions, including damage to the following organs:
- bone marrow
- gastrointestinal tract
Methotrexate may also cause some issues when mixed with other drugs and substances, including:
- oral antibiotics
- aspirin and other nonsteroidal anti-inflammatory drugs
- proton pump inhibitors
- antifolate drugs
- penicillin or sulfonamide antibiotics
- products that may affect the liver, including herbal medicines
- low levels of folic acid
- probenecid, which treats gout
- foods that are damaging to the kidneys
- nitrous oxide administered as anesthesia
Other possible treatments
When it comes to treating psoriasis, there are various alternatives to chemotherapy. Other medications and light treatment are among them.
While methotrexate is a common first-line treatment for psoriasis, alternative medications are just as beneficial, if not more so. Inflammatory disorders, such as rheumatoid arthritis, may also benefit from the following treatments:
- disease-modifying antirheumatic drugs, including cyclosporine
- anti-tumor necrosis factor drugs, including adalimumab, infliximab, and etanercept
- systemic retinoids
- apremilast, a phosphodiesterase-4 inhibitor
- interleukin (IL)-17 and IL-23 inhibitors, such as secukinumab and risankizumab
Other light therapies are available to treat psoriasis. The recommended treatment may depend on the type and severity of psoriasis. Some of these include:
- Narrowband ultraviolet B (NB-UVB): This treatment is more effective for larger areas of psoriatic lesions.
- Pulsed dye laser: This therapy is effective for nail psoriasis and topical plaque psoriasis.
- Photodynamic therapy, intense pulsed light: This treatment is effective for chronic plaque psoriasis and nail psoriasis.
- Light-emitting diodes: This therapy is effective for chronic plaque psoriasis and nail psoriasis.
- Red and blue light near-infrared: Doctors use these treatments to treat plaque psoriasis.
- Excimer laser or lamp: This therapy is effective for nail psoriasis.
- Broadband ultraviolet B: This treatment is generally safer than PUVA but may not be as effective for more severe psoriasis.
- Sunbath: This therapy is effective for chronic plaque psoriasis.
In the treatment of psoriasis, both PUVA and NB-UVB are beneficial. However, dermatologists favor NB-UVB as the first-line phototherapy due to the possible risks.
Learn more about light therapy for psoriasis here.
Chemotherapy medications have been repurposed to treat moderate-to-severe psoriasis, allowing patients to achieve remission. Doctors, on the other hand, often use a lesser dosage than when treating cancer.
Although there is no cure for psoriasis at this condition, effective therapies can assist to alleviate its symptoms.
With the assistance of a medical practitioner, it is also feasible to manage the adverse effects of prescription medications. The majority of people with psoriasis can discover a treatment that will help them live a better life.