Its caused by prolactin. Since prolactin counteracts dopamine and vice versa. When the other one is high, the other one is low. Dopamine is what gives us libido, and the prolactin after surge orgasm makes our libido disappear in an instant.
You can take supplements that decrease libido. But, since they lower dopamine, these supplements will also lower your motivation to achieve anything and they make you less energetic. Like chasteberry, antipsychotic medication, etc.