There is usually no reaction to the use of nifurtimox, but if you are allergic to the drug, local itching may occur after use. If there was no itching before and significant itching occurs after using the drug, you need to stop using the drug in time and consider that you may be allergic to its main component, metronidazole. Under normal circumstances, after the use of the drug, because the drug will also flow out part, this time can appear increased secretion, do not need to worry. It is recommended to use the drug at night before going to bed, so that the effect of gravity will not cause the drug to melt and then quickly flow out, can stay in the body for a longer period of time in order to better function, the use of drug treatment during the need to avoid intercourse.