977Adverse Effects: Of drugs and medications-including allergy, overdose, reactions
Accidents, Poisonings and Violence
What this reference tells you
977 is an Ontario diagnostic code describing “Adverse Effects: Of drugs and medications-including allergy, overdose, reactions.” It supports the diagnosis field of a claim and is distinct from the fee code identifying the service.
Before using this code
Confirm the current Ministry publication, the patient and provider context, the date of service, and documentation supporting the claim. A searchable reference does not establish eligibility or guarantee payment.