In the name of Allah, the most Beneficent, the most Merciful. 

Answer

After having intercourse one should at least wash the hands and rinse the mouth before eating, drinking and cooking. It is undesirable (makrooh tanzihi) to drink (only the first gulp will be makrooh) before rinsing the mouth as the water of the first gulp will be classed as ma’a musta’mil (used water). It is also undesirable to eat and cook (before washing the hands) as it is likely that the hands will have impurity on them, therefore it is preferable to wash the hands before eating and cooking. (Raddul Muhtar, Vol, 1, P 129)

Only Allah knows best.

Sayeedur Rahman

Darul Ifta, Birmingham