Though the pharmacological half-life of exogenous NPY, other agonists, and antagonist is still obscure, the effects are not long lasting and the rat body employs an excellent ability to regulate and normalize abnormal NPY levels and therefore food consumption.
Eksogeense NPY, agonistide ja antagonistide farmakoloogiline poolestusaeg on ikka veel kahtluse all, nende mõjud pole kauakestvad ja roti keha suudab reguleerida ja normaliseerida ebanormaalset NPY kogust ja seega ka toidutarbimist.