Abstract: We included 10 randomised controlled trials (with a total of 1049 participants) of moderate to high risk of bias. All studies involved different comparisons, none had a placebo group. In 1 trial plasma exchange plus prednisone gave significantly better disease control at 1 month (0.3 mg/kg: RR 18.78, 95% CI 1.20 to 293.70) than prednisone alone (1.0 mg/kg: RR 1.79, 95% CI 1.11 to 2.90), while another trial showed no difference in disease control at 6 months. No differences in disease control were seen for different doses or formulations of prednisolone (one trial each), for azathioprine plus prednisone compared with prednisone alone (one trial), for prednisolone plus azathioprine compared with prednisolone plus plasma exchange (one trial), for prednisolone plus mycophenolate mofetil or plus azathioprine (one trial), for tetracycline plus nicotinamide compared with prednisolone (one trial). Chinese traditional medicine plus prednisone was not effective in one trial. There were no significant differences in healing in a comparison of a standard regimen of topical steroids (clobetasol) with a milder regimen (RR 1.00, 95% 0.97 to 1.03) in one trial. In another trial, clobetasol showed significantly more disease control than oral prednisolone in people with extensive and moderate disease (RR 1.09, 95% CI 1.02 to 1.17), with significantly reduced mortality and adverse events (RR 1.06, 95% CI 1.00 to 1.12). Very potent topical steroids are effective and safe treatments for BP, but their use in extensive disease may be limited by side-effects and practical factors. Milder regimens (using lower doses of steroids) are safe and effective in moderate BP. Starting doses of prednisolone greater than 0.75 mg/kg/day do not give additional benefit, lower doses may be adequate to control disease and reduce the incidence and severity of adverse reactions. The effectiveness of adding plasma exchange, azathioprine or mycophenolate mofetil to corticosteroids, and combination treatment with tetracycline and nicotinamide needs further investigation.

Plain-language summary: Three new studies were included in this update of the review published in 2005 making a total of 10 randomised controlled trials with a total of 1049 participants. All studies involved different comparisons, none had a placebo group. Different doses and formulations of corticosteroids plus azathioprine showed no significant differences in disease control, although azathioprine reduced the amount of prednisone required for disease control. There were no significant differences in healing or disease-free intervals in participants taking azathioprine compared with mycophenolate mofetil, or in disease response comparing tetracycline plus nicotinamide with prednisolone. One small study using Chinese traditional medicine, 'Jingui Shenqi Pill' (JSP), plus prednisone did not show any benefit in favour of adding this traditional Chinese herbal remedy. Most of the deaths were in participants taking high doses of oral corticosteroids. The review of trials concluded that lower doses of oral steroids and strong steroid creams seem safe and effective. However, the use of steroid creams in extensive disease may be limited by side-effects and the practicality of applying creams to large areas of the skin. Milder regimens of topical steroids are safe and effective in moderate BP. More research is needed on treatments for BP, in particular, the effectiveness of adding plasma exchange, azathioprine or mycophenolate mofetil to corticosteroids, and the treatment with tetracyclines and nicotinamide.