Hello.
Thank you for your query at DoctorSpring.com.
No. Any extended release pill should not be cut. These pills are specially coated so that the drug is released slowly over an extended period. Cutting them will damage this coating and will cause the drug to be released faster and its duration of action will be reduced.
Since some extended release tablets contain a larger amount of the drug, ingestion of such a pill which has been cut may cause symptoms of an overdosage.
In your case, if you cut a Seroquel 50 mg into half, a larger amount of drug than needed will reach your bloodstream and the duration of its action will also be reduced. So this is generally not safe or recommended.
I hope this was helpful. Let me know if you have further queries.
Regards.