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It is permissible to use such drugs only when certain conditions are implemented:
1- That using the drug becomes a necessity.
2- A trustworthy doctor must testify that this drug is needed and useful to the patient.
3- To use only the portion needed for treatment.
4- There is no other medicine that can be taken other than it.
5- Its harm must not exceed its benefit! Addiction is the worst harm that can be caused by it.