A study of rivastigmine liposomes for delivery into the brain through intranasal route KARTHIK ARUMUGAM GANESA SUNDARARAJAN SUBRAMANIAN* SURULIVEL RAJAN MALLAYASAMY RANJITH KUMAR AVERINENI MEKA SREENIVASA REDDY

with low oral bioavailability due to to extensive gastrointestinal breakdown or high hepatic first-pass effect. Intranasal delivery of drugs to reach the system has been widely studied and a number of reports is available in the literature (1). The concentration-time profiles of drugs achieved after nasal administration are often similar to those after intravenous administration, with resultant rapid onset of pharmacological activity (2). Intranasal delivery provides a convenient route for the delivery of drugs into brain. Around 35–40 substances have been reported to reach the central nervous system after nasal administration in experimental animals, e.g., carbamazepine (3), dopamine (4), neurotoxic metals (5), local anaesthetics (6), carboxylic acids (7) and the nerve growth factor (8). The olfactory region of the nasal passages has unique anatomic and physiologic attributes that provide both extracellular and intracellular pathways into the CNS bypassing the blood-brain barrier (9, 10). Alzheimer’s disease (AD), a progressive neurodegenerative