If homeopathic remedies do not involve using impure or haram things or any illegal method of cure and they do not cause any damage to the patient's health, there would be no problem in it.
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The same question has been forwarded to the offices of some grand religious authorities and the answers which we have received are as under:[1]
Grand Ayatollah Makarem Shirazi (may Allah grant him long life):
If it does not cause any damage to the health of the ailing person, there is no problem.
Grand Ayatollah Sistani (may Allah grant him long life):
There is no objection in it per se.
Grand Ayatollah Noori Hamedani (may Allah grant him long life):
If it does not involve any haram thing, there is no objection.
Grand Ayatollah Saafi Gulpaigani (may Allah grant him long life):
Remedies through the said method would be permissible on the condition that halal medicines are used. As for using haram medicines, it would be permissible to use them only when cure or remedy is exclusively restricted to it in which case it is permissible to use them to the necessary extent only.
Ayatollah Hadavi Tehrani  (may Allah grant him long life):
If homeopathic remedies do not involve using impure or haram things or any illegal method of cure and they do not cause any damage to the patient's health, there would be no problem in it. Link to Isteftaat Website.

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