Sooner or later the junkie must have their juice taken from them and while it may look awful if they writhe on a bed, in the same way, when these criminals are cut off from their chemical posion they will throw some tantrums, but the short term effects of that (as they over time are rounded up and either deported or jailed) will be miniscule next to the long-term damage they will cause if left unobstructed.
Yes, the junkie needs to be put in confinement until they go through a medically-supervised detox (cold turkey is a dangerous way). A person who relapses after going through the process, gets a prison sentence. The strategy is to cut the supply of drugs (border wall) and reduce the user population. The Cartels will be livid with the squeeze. The American people will be happy.