Low solubility causing low dissolution in gastrointestinal tract is the major problem for drugs meant for systemic action after oral administration, like cinnarizine. Pharmaceutical products of cinnarizine are commercialized globally as immediate release preparations presenting low absorption with low and erratic bioavailability. Approaches to enhance bioavailability are widely cited in the literature. An attempt has been made to review the bioavailability complications and clinical therapeutics of poorly water soluble drug: cinnarizine. The interest of writing this paper is to summarize the pharmacokinetic limitations of drug with special focus on strategies to improvise bioavailability along with effectiveness of novel dosage forms to circumvent the obstacle. The paper provides insight to the approaches to overcome low and erratic bioavailability of cinnarizine by cyclodextrin complexes and novel dosage forms: self-nanoemulsifying systems and buoyant microparticulates. Nanoformulations need to systematically explored in future, for their new clinical role in prophylaxis of migraine attacks in children. Clinical reports have affirmed the role of cinnarizine in migraine prophylaxis. Research needs to be dedicated to develop dosage forms for efficacious bioavailability and drug directly to brain. 1. Introduction Low aqueous solubility of drug has always presented major obstacle towards the development of drug delivery systems which often compromises patient compliance. Oral route is thought to be common and easy for drug administration. On oral administration of drug in its dosage form, it is expected to dissolve and release the drug into the gastrointestinal fluid before the absorption [1]. Poor solubility may limit the dissolution of drug in gastrointestinal tract resulting to low bioavailability that can pharmacologically affect the therapeutic efficacy of drug [2]. The drugs belonging to BCS class II and IV particularly fall in this category and have been extensively researched molecular optimization and development of novel efficacious dosage forms. Cinnarizine, (E)-1-(diphenylmethyl)-4-(3-phenylprop-2-enyl) piperazine (Figure 1), molecular formula: C26H28N2 and molecular weight: 368.51？g/mol, is white or almost white powder. Originally obtained from woodreed roots (Cinna), cinnarizine was first synthesized by Janssen Pharmaceutica in 1955 and marketed in 1958 under the brand name Stugeron. It is a weak base with poor aqueous solubility. According to a paper the solubility of cinnarizine is highly pH dependent, that is, 0.29？mg/mL at pH 2,
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