Brief Answer:
yes, it is harmful if taken for prolonged time.

Detailed Answer:

Thanks for writing to health care magic.
Inj Haldol contains Haloperidol,a drug used for the treatment of Schizophernia.Since your suffering from schizophernia you have to take this drug for prolonged period of time. As with any other drug it too has side effects, but the useful effects of this drug outweigh the side effects. Prolonged use of any drug produce long term side effects and Halodol is no exception, but your physician is the best judge and he/she knows for how much time you can continue with this drug without any serious side effects.
Hope this answers your question.
Let me know if you have any more queries.
Take care and best regards
Dr Sadiq

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