The primary focus of this paper is to present a general view of the current applications of fuzzy logic in
medical analogy of consumption of drugs. The paper also deals with the origin, structure and
composition of fuzzy sets. The authors particularly review the medical literature using fuzzy logic.
Fuzzy set theory can be considered as a suitable formalism to deal with the imprecision intrinsic to
many real world problems. Fuzzy set theory provides an appropriate framework for the representation
of vague medical concepts and imprecise modes of reasoning. The authors present two concrete
illustrations to investigate the impact of the risk related to drug addictions, like smoking and alcohol
drinking and thereby highlighting the social problem related to health.
Key words: Estimation, classical set, validation, diagnostic test.