Is piperine the same as black pepper?
No. Piperine is one constituent of black pepper, and an isolated or concentrated piperine product is not equivalent to seasoning.
The short answer
Black peppercorn contains piperine along with volatile oils and many other compounds. Isolated piperine can be supplied at concentrations far beyond ordinary food exposure and may alter medicine absorption or metabolism. Review concentrated use with a pharmacist when taking prescriptions.