(Fatwa: 1140/1083=D/1429)
It is allowable to use hair tonic containing alcohol but if the mentioned alcohol is made of grapes, raisin, dates and dried dates, then even a drop of it is impure. If the aforesaid oil contains such kind of alcohol then it is not pure and it will make the hair and clothes impure; therefore in this case, it is better not to use such oil. However, if the alcohol is made of other things (like potato, wheat etc) other than the above-mentioned four things, then it is pure and lawful to use it externally. If it is not known what alcohol is made of, then it is better to shun form using oil containing alcohol.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband