Receptor antagonists can be competitive (or reversible), and compete with the agonist for the receptor, or they can be irreversible antagonists that form covalent bonds (or extremely high affinity non-covalent bonds) with the receptor and completely block it.
Os antagonistas de receptor poden ser competitivos (ou reversibles), que compiten co agonista polo receptor, ou antagonistas irreversibles, que forman enlaces covalentes (ou ás veces non covalentes pero de afinidade moi alta) co receptor e bloquéano completamente.