Adverse effect of cannabis, initial encounter

This code signifies a patient experiencing an unintended and undesirable reaction to cannabis, such as acute intoxication, psychosis, or severe anxiety, during their first presentation for this specific adverse event. It indicates that the cannabis itself, rather than another substance or underlying condition, is the direct cause of the adverse effect.

Apply this code when a patient presents to an emergency department or clinic for the first time due to symptoms directly attributable to cannabis use, such as severe panic attacks, hallucinations, or intractable nausea and vomiting following cannabis ingestion. This code is appropriate for initial evaluations and treatments for these acute adverse reactions.

• Always assign an additional code for the specific manifestation of the adverse effect (e.g., F12.129 for cannabis intoxication with unspecified behavioral disturbance).
• Ensure documentation clearly links the adverse effect to cannabis use and specifies it as the initial encounter.
• Distinguish from poisoning (T40.711-) which implies an overdose or toxic effect, versus an adverse effect which is a non-toxic, undesirable reaction at therapeutic or recreational doses.