In 1971 daraprim (pyrimethamine) compound tab. (quinine dihydrochloride tab) was available in india. What's and alternative?

It is not available. It is available by the FDA for only malaria but we use dto use a lot of nocturnal leg cramps but it is not FDA approved for this now For leg cramps one can try magnesium under a physicians monitoring. It can cause diarrhea and may help leg cramps if that is what you are asking about.