Font Size

Understanding Psoriasis Medications (cont.)

Systemic Agents


Acitretin (Soriatane) is used for severe psoriasis.

  • How retinoids work: Retinoids are used to control psoriasis and reduce the redness of the skin. They can be used in combination with medically controlled ultraviolet phototherapy to minimize the dose of each.
  • Who should not use these medications: Individuals who are allergic to retinoids, are pregnant, or are breastfeeding should not take retinoids.
  • Use: Acitretin is in a capsule. It is usually taken once a day by mouth with food. Therapy is continued until plaques have decreased.
  • Drug or food interactions: Acitretin increases methotrexate toxicity when both are used together. This medicine can interfere with oral contraceptives ("minipill"). Do not use alcohol while taking acitretin and for two months after stopping the medicine. Alcohol causes the drug to convert to a long-acting form and could prolong the risk of birth defects.
  • Adverse effects: Women of childbearing age must use effective birth control measures. Birth control must be continued for at least three years after the woman stops taking acitretin because the drug stays in the body for a very long time and will hurt unborn babies. Caution must be used if the individual has kidney or liver problems. Contact the doctor immediately if one develops a rash or skin or vision changes.


Methoxsalen (Oxsoralen-Ultra) and trioxsalen (Trisoralen) are commonly prescribed psoralens. Psoralens are a class of drugs that make the skin more sensitive to light and the sun. Psoralens are used with ultraviolet light therapy. This therapy, called PUVA, uses a psoralen with ultraviolet A (UV-A) light to treat psoriasis when it covers a large area of the skin or is severe. More than 85% of patients report relief of disease symptoms with 20-30 treatments.

  • How psoralens work: Psoralens have no effect unless combined with ultraviolet light therapy. They are used with the light therapy to slow skin-cell overproduction.
  • Who should not use psoralens: Individuals with the following conditions should not take psoralens:
    • Psoralen allergy
    • History of skin cancer
    • Photosensitivity diseases such as porphyria, lupus erythematosus, xeroderma pigmentosum, or albinism
    • Inability to tolerate prolonged standing or heat, for example, in those with heart disease
    • Pregnancy
    • Children younger than 12 years of age
  • Use: Psoralens are taken by mouth 45-60 minutes prior to UVA exposure. Occasionally, psoralens have been applied to the skin in creams, lotions, or bath soaks. This requires close medical monitoring due to the propensity to produce burns. Treatments frequency should not be shorter than 48 hours.
  • Drug or food interactions: Other photosensitizing drugs, such as phenothiazines, bacteriostatic soaps, sulfonamides, tetracyclines, thiazides, or even perfumes may increase the skin's sensitivity to the sun or may cause other problems. Before taking psoralens, let the doctor know if any other medicine are being taken.
  • Adverse effects: A doctor experienced with PUVA therapy should supervise the use of these medicines. Severe burns can occur from sunlight or the ultraviolet light while taking psoralens. These drugs cause sensitivity to sunlight and increase the risk of sunburn, skin cancer, and cataracts. After each treatment, avoid going out in the sun for at least 24 hours. Cover up with clothing and use sun block if the skin will be exposed to the sun. A certain type of sunglasses are recommended to protect the eyes after treatments. Treatment usually causes reddening of the skin for 24-48 hours. However, contact the doctor if severe redness, blisters, fever, or peeling occurs.
Medically Reviewed by a Doctor on 7/14/2016

Must Read Articles Related to Understanding Psoriasis Medications

Nail Psoriasis
Nail Psoriasis Psoriasis is a common condition. learn more >>

Patient Comments & Reviews

The eMedicineHealth doctors ask about Psoriasis Medications:

Psoriasis Medications - Treatment

What medication has worked best for your psoriasis?

Psoriasis Medications - Topical

What topical medication has helped to alleviate your psoriasis symptoms and signs?

Psoriasis Medications - Oral

What oral medications have helped your psoriasis symptoms and signs?

Read What Your Physician is Reading on Medscape

Psoriasis »

Psoriasis is a chronic, noncontagious, multisystem, inflammatory disorder.

Read More on Medscape Reference »

Medical Dictionary