Development and formulation of a new natural product for the treatment of pityriasis versicolor and skin dermatophyte infections

Abstract

Tinea versicolor (TV) and skin dermatophytes (SD) infections are common diseases widely spread in tropical areas and among poor populations. There are some chemical drugs used in the treatment of TV and S.D infections. These drugs have side effects; especially oral drugs which have toxic effects on liver and kidneys. Some are very expensive and recurrence rate of the disease is high. The aim of this study was to prepare a new, non expensive, effective and safe pharmaceutical formulation for treatment of TV and SD infections using a naturally available volcanic stone extract. This volcanic stone is native to Yemen where it is used traditionally for treatment of TV and SDinfections by soaking in water and wiping the affected areas of the skin. In this study chemical analysis was done for the stone which identified its constituents and the amount of each constituent. In vitro microbiological studies were done to know the effect of the stone extracts on cultures of differentfungi and bacteria. Comparative studies were carried out to investigate the microbiologicalactivity of the stone extracts with other drugs used for treatment of fungi infections. The results achieved showed high microbiological activity of stone extracts against TV and other dermatophytes infections. The stone extract was then formulated in a suitable pharmaceutical formulation (aqueous cream) and the physical and chemical properties of this formulation were determined. The stability of the finished formulation was carried out. iv Pharmacological studies of the stone extract were done for the smooth muscle receptors in the small intestine and aortic muscle from the rabbit and on the receptors ofthe skeletal muscle from the frog, and also on the receptors of the uterus muscle from the rat. The results of these studies showed that there are no pharmacological effects on these receptors. Toxicological studies of the stone extract (100 mg/kg) were tried on twelve rats; six were used as control and the others six as test. The drug was given to the test group for twentyone days (sub chronic study) in high doses (100 mg/kg) and after that blood was taken from both groups. Blood was analyzed for all parameters and different enzymes and the results were compared with the control groups. The results showed that there were no significant difference between the two groups this indicate that the drug is free of toxic effects. The five important organs of the control rat (liver, Kidney, heart, small intestine and spleen) were taken. Specimens were prepared for histopathological studies. The results confirmed that there is no damage or effect on these organs. Clinical trials using the pharmaceutical formulation were carried out in Sudan after the approval of the study by the Ethics Committee of the Research Administration, Federal Ministry of Health, Sudan. Clinical comparative studies were done on one hundred volunteers; fifty were treated with clotrimazolecream and the other fifty with the new cream formulation. The results were analyzed and statistically compared using SPSS. This showed that the new creamformulation was effective for the treatment of TV and other S.D infections with no recurrences