It should, but I absolutely wouldn't suggest making it yourself, it can be extremely dangerous due to the flammability of the butane.
For Cancer, you want the highest THC strain possible, and if he has any pain associated, using a strain with a 1:1 THC CBD ratio, or just using an additional strain that is high CBD will help with any pain he may have.
Yes, I also think that doing the grain alcohol method is safest and most effective.
And I recommend supplementing this with raw Cannabis (fresh and/or dried). The activated oil helps to fight symptoms (short-term healing), while the raw nutrients go after the source of the problem (long-term prevention).
The more Cannabis that is consumed, the more efficiently your dad's body will be able to heal itself.
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