What is the ruling on using hashish oil for hair, and what is the reason for its prohibition if it is deemed unlawful?

If the aforementioned oil intoxicates or stupefies, then it is not permissible to use it or to seek treatment with it, based on the Prophet’s (peace be upon him) saying: “Every intoxicant is unlawful.” And a liquid intoxicant is considered impure by the majority of scholars. However, if it does not intoxicate, then there is no objection to using it.