A rare illness is an illness that affects a tiny low share of the population. In some components of the globe, Associate in a nursing orphan illness may be a rare illness whose rarity suggests that there's a scarcity of a market massive enough to realize support and resources for locating treatments for it, except by the govt. Granting economically advantageous conditions to making and merchandising such treatments. Orphan medication square measure ones thus created or sold. An orphan drug may be a pharmaceutical agent that has been developed specifically to treat a rare medical condition, the condition itself being observed as Associate in nursing orphan illness. The assignment of orphan standing to an illness and to any medication developed to treat it's a matter of public policy in several countries and has resulted in medical breakthroughs which will not have otherwise been achieved because of the economic science of drug analysis and development.