Fiqh-us-Sunnah Volume 4, Funerals and Dhikr, Fiqh 4.006.
The majority of scholars hold that the use of wine and other prohibited things as medicine, is unlawful. They base their arguments on the following hadith:
Wa’il ibn Hujr al-Hadrami reported that, “Tariq ibn Suwaid asked the Prophet, peace be upon him, if he could use liquor as medicine. The Prophet replied: ‘It is not a cure, but a disease’.” (Muslim, Abu Daw’ud, and Tirmizhi.)
Umm Salamah, the wife of the Prophet, peace be upon him, reports that he once said: “Allah has not placed a cure for your diseases in things that He has forbidden for you.” (Reported by Baihaqi; Ibn Hibban considers this hadith to be sound. Bukhari has also related it on the authority of Ibn Mas’ud.)
Abu ad-Darda reported that the Prophet, peace be upon him, said: “Allah has sent down both the malady and its remedy. For every disease He has created a cure. So seek medical treatment, but never with something the use of which Allah has prohibited.” (Reported by Abu Daw’ud. Among the narrators of this hadith we find Isma’il ibn ‘Aiyash, who is considered trustworthy by the Syrians, but regarded as a weak narrator by the scholars of Hijaz.)
Abu Hurairah narrated: “The Messenger of Allah, peace be upon him, prohibited the use of a harmful medicine, namely, poison.”(Ahmad, Muslim, Tirmizhi, and Ibn Majah.)
Using a few, unnoticeable drops that cannot induce intoxication, is not prohibited, provided they are a part of a compound medicine. For example, the use of a small amount of pure natural silk in a woven fabric, as explained in al-Manar.