Conventional synthetic disease-modifying antirheumatic drugs for peripheral psoriatic arthritis
The conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) methotrexate, sulfasalazine and leflunomide are used by specialists for peripheral psoriatic arthritis and may benefit both the arthritis and skin disease.
There is limited evidence to guide csDMARD choice in peripheral psoriatic arthritis, and comparative efficacy data are lacking. Drug choice may be influenced by patient preference and factors (including comorbidities, drug interactions and adverse effects). The risk of drug-induced abnormalities in liver biochemistry may be higher in people with psoriatic arthritis than in other inflammatory arthropathies.
For considerations in the management of csDMARD therapy (including monitoring, screening for infection, and vaccination), see Principles of immunomodulatory drug use.
The dosage of methotrexate for peripheral psoriatic arthritis is:
1methotrexate 10 to 25 mg orally, on one specified day once weekly methotrexate methotrexate methotrexate
OR
1methotrexate 10 to 25 mg subcutaneously, on one specified day once weekly methotrexate methotrexate methotrexate
PLUS with either of the above
folic acid 5 to 10 mg orally, weekly (not on the same day as methotrexate). folic acid folic acid folic acid
The usual dosage of sulfasalazine for peripheral psoriatic arthritis is:
sulfasalazine (enteric-coated) 500 mg orally, daily, increasing gradually up to 1500 mg twice daily. sulfasalazine sulfasalazine sulfasalazine
The usual dosage of leflunomide for peripheral psoriatic arthritis is:
leflunomide 10 to 20 mg orally, daily. leflunomide leflunomide leflunomide
Ciclosporin has been demonstrated in clinical trials to benefit psoriatic arthritis and skin disease. Dose-limiting adverse effects are significant, especially kidney impairment and hypertension.
Apremilast, a phosphodiesterase 4 (PDE-4) inhibitor listed on the Pharmaceutical Benefits Scheme (PBS) for the treatment of psoriasis, may be continued in some people for treatment of arthritic features; however, it is not PBS listed for psoriatic arthritis.
Other csDMARDs, including azathioprine and hydroxychloroquine, have been used in the treatment of psoriatic arthritis, with anecdotal evidence of benefit. Caution is recommended with the use of hydroxychloroquine in psoriatic arthritis because of the risk of inducing a severe flare of skin disease.