Hello dear,

Biopharmaceutics is a major branch in pharmaceutical sciences which relates between the physicochemical properties of a drug in dosage form and the pharmacology, toxicology, or clinical response observed after its administration .
Drug efficacy and safety are dependent on the dosing regimen.
The optimal dosage and dosing intervals can be quite different for different drugs.
Moreover, for a single drug, the optimal dosage can be different widely between patients .

Pharmacodynamics refers to the relationship between drug concentration at the site of action and the resulting effect, including the time course and intensity of therapeutic and its adverse effects. Studies are designed to investigate all primary and secondary effects related to the desired therapeutic effects, extensions of the therapeutic effect that might produce toxicity at higher doses, and effects related to interactions with other drugs.

Pharmacokinetics

Pharmacokinetics refers to the study of the time course of a drug within the body (extent and duration of systemic exposure to the drug) and also incorporates the process about the drugs Absorption, Distribution, Metabolism, Excretion(ADME) pattern. In general, pharmacokinetic parameters are derived from the measurement of drug concentrations in blood or plasma.

Biopharmaceutics will have theory ,
And pharmacokinetics will have all derivations,
So when you study properly about biopharmaceutics then only you can understand pharmacokinetics clearly,
And for understanding kinetics you should have some command on derivations and also some formulas of mathematics for calculations,

So first study biopharmaceutics and then go with kinetics ,
And best books are biopharmaceutics and pharmacokinetics by Leon shargeal, and brahmankar ,

Practice everyday a derivation, and practice compartment modelling everyday,
Never ever delay the Bppk topics till exams arrive ,
You can crack that subject with daily practice and you can't score well if you sit with all topics one day before exams ,
Prepare well,
Practice every day,
Correlate bp with pk ,
And all the best for your preparation for BPPK !