Despite significant advancements in CNS research, CNS illnesses are the most important and serious cause of mental disability worldwide. These facts show a tremendous unmet demand for effective CNS medications and pharmacotherapy since it accounts for more hospitalizations and extended care than practically all other disorders combined. The site-targeted kinetics of the brain and, pharmacodynamics of CNS effects are determined/regulated by various mechanisms after the dose, including blood-brain barrier (BBB) transport and many other processes. These processes are condition-dependent in terms of their rate and extent because they are dynamically controlled. For effective therapy, drugs should access the CNS "at the right place, time, and concentration". Details on inter-species and inter-condition variances are required to translate target site pharmacokinetics and associated CNS effects between species and illness states, improving CNS therapeutics and drug development. The present review encircles a short discussion about the barriers that affect effective CNS treatment and precisely focuses on the pharmacokinetics aspects of efficient CNS therapeutics.