How long after applying Metronidazole gel can I go to bed?

You did not include the name of the preparation in the question. If your question is about Metronidazole, which is tagged, please read on. The manufacturer does not specify a minimum time from the moment the gel is applied to the skin until it lies on the bed. Probably, it is enough to wait until the applied gel dries. The time necessary for the drug layer to dry depends, m.in, on the lubricated surface of the skin and can take several minutes. Metronidazole gel is usually used 2 times a day, in the morning and in the evening before bedtime. After applying the gel, you can additionally use cosmetics that do not clog the pores of the skin and do not have astringent properties: https://www.gdziepolek.pl/produkty/48756/metronidazol-jelfa-zel/apteki