The proliferation of illicit drug markets facilitate the flow of doubtful quality products of uncertain origin to the most disadvantaged populations. The consumption of counterfeit medicines that do not meet international standards can explain the repeated treatment failures, the development of tolerance or even addiction to drug observed after taking generic drugs. High consumption of compressed ibuprofen, second most consumed analgesic after paracetamol led us to a comparative study of physicochemical and dosage parameters of the generic pill ibuprofen 400 mg sold in the formal and informal market in Douala according to international pharmacopoeia. The results show that non-normalised medicines are present both in the formal and in the informal circuit. Each of the circuits presented a compliance rate of about 80%. Moreover, the presence of the same batch of tablet, from the same laboratory both in the formal and in the informal circuit would be a proof that the informal market of drugs "gazon" supply is assured by both the smuggling and the formal distribution sector. It is imperative that Governments in countries such as Cameroon through health and safety officers take radical decisions to control the quality, stability and efficiency of drugs introduced in their countries.