Generally drugs can act on the level of different biological membranes as well as inside the cells that are limited by membranes. Even in the latter situation, drugs must still interact with the membrane in order to cross it and reach their targets. For this reason, the efficiency of drugs to interact with the membranes constitutes one of the most important pharmacological features playing an essential role in their biological activity. Membranes are the gathering place of many proteins and lipids, and are the structures where most cellular activities occur. Although drugs bind to proteins and regulate their activity, the membrane lipid phase is no less important. Great part of compounds studied induces structural changes in the lipid phase resulting structural defects, which in turn disturb membrane function and indirectly modulate membrane proteins. This paper reviews the clinical significance of drug-membrane interaction studies with a special focus in the lipidic components of the membrane and reinforcing the importance of these studies in the field of medicinal chemistry since they constitute stimulating opportunities for understanding drugs mode of action and toxic effects and cannot be overlooked during drug design and synthesis.