Abstract
Although hydroxychloroquine is recommended for all the patients with systemic lupus erythematosus without contraindications, one third of lupus patients are not taking this important medication. Overcoming some of non-organ threatening side effects can lead to better drug survival rate and then improvement of overall outcome.
Since the approval of hydroxychloroquine in 2015 in Japan, we prescribed it to more than 200 patients of lupus in our institution. It is usually well-tolerated, but it is also true that some developed adverse effects which kept them from continuing it. As we believed that hydroxychloroquine should be continued based on the risk-benefit ratio in case of minor adverse events, such as non-severe drug eruption and gastrointestinal intolerance, we decided two systematic approaches for these problems.
For urticaria and erythematous drug rash, we first performed Drug Lymphocyte Stimulation Test (DLST), then offered oral desensitisation if the result is negative. Five patients agreed to undergo oral desensitisation over 5 weeks with crashed hydroxychloroquine tablets in conjunction with once daily levocertirizine 5 mg at night. Desensitisation courses were started on Monday and patients were informed to contact allergologist if skin rash or pruritus emerged. All the five patients successfully went through the graded increment of hydroxychloroquine, and then continued it without the anti-histamine.
For diarrhoea, hangeshashinntou was added. Hangeshashinto, i.e. a Pinellia heart- draining decoction; in Chinese: ban xia xie xin tang), is widely administered in Japan to prevent diarrhoea induced by chemotherapy and immunosuppressive agents such as irinotecan and mycophenolate mofetil. The mechanism is reported to the inhibitory effect of glucuronidase-mediated de-conjugation. Two patients who stopped hydroxychloroquine due to diarrhoea became able to resume it with hangechashintou.
In conclusion, desensitisation of hydroxychloroquine and co-administration of hangeshashintou resulted in better tolerance of the anti-malarial in Japanese patients without serious side effects.
