Severe cutaneous adverse drug reaction to leflunomide: a report of five cases.

Medications used to treat human ailments are known to cause cutaneous reactions which may vary in their severity. Leflunomide, an immunomodulating agent recently introduced to treat rheumatoid arthritis, is reported to cause severe cutaneous reactions. We are reporting five such cases. All our patients were started on leflunomide for rheumatoid arthritis, 4-6 weeks before the onset of cutaneous reaction and were admitted to the hospital with the common complaints of fever, skin rash and generalized weakness. All of them had characteristic pattern of events such as delayed onset of reaction, widespread and long lasting skin rash and internal organ involvement. These features suggest a possibility of drug hypersensitivity syndrome to leflunomide. Careful dosing and periodic monitoring of patients treated with leflunomide for possible adverse drug reaction is recommended.

Sparfloxacin induced toxic epidermal necrolysis.

Toxic epidermal necrolysis (TEN) is a life-threatening cutaneous adverse drug reaction. TEN is known to occur with the fluoroquinolone class of antibiotics, but only four cases of sparfloxacin induced TEN have been reported to the WHO database. This is another case report of sparfloxacin induced TEN.

Altered biological distribution and decreased neuromuscular toxicity of niosome encapsulated vincristine.

Effects of encapsulation within niosomes (nonionic surfactant vesicles) on the biological distribution and toxicity of vincristine-a widely used anticancer drug have been investigated. Plasma kinetics, tissue distribution profile and neuromuscular toxicity of niosomal vincristine (NVCR) were compared with those of free vincristine (FVCR). NVCR was cleared from the plasma much more slowly [t1/2(beta) = 1.388 hr] than FVCR [t1/2(beta) = 0.74 hr]. Over the 48 hr period of experiment, the niosome formulation delivered significantly more drug to the plasma compartment than FVCR and resulted in reduced accumulation of drug in gut and skeletal muscle. Encapsulation caused a marked alteration in the tissue disposition of the drug. NVCR was less toxic both in terms of mortality and morbidity. Importantly, histopathological studies of skeletal muscle, spinal cord and sciatic nerve of NVCR treated albino wistar rats demonstrated the less toxic potential of encapsulated vincristine. Further, the biochemical studies, estimation of enzymes plasma creatine phosphokinase and lactate dehydrogenase, confirmed the safety profile of NVCR. The decreased partitioning of NVCR to non active sites resulted in a significant amelioration of the toxic side effects, gastrointestinal and myological in particular, of the drug. The results indicate that the delivery of vincristine by encapsulating it in niosomes offer an efficient means of decreasing its toxic effects.