Drug-induced headache, not elsewhere classified, intractable

This code signifies a headache directly caused by the use of a medication, which is resistant to standard treatment interventions. It indicates that the headache is chronic or severe and has not responded adequately to therapeutic measures. This condition is distinct from headaches that are a symptom of another underlying disease.

Use this code when documentation clearly states a headache is drug-induced and explicitly describes it as "intractable," "refractory," or "resistant to treatment." This often occurs in cases of medication overuse headache (MOH) where the patient continues to experience severe headaches despite attempts to manage the condition. Supporting documentation should detail the medication suspected of causing the headache and the failed treatment attempts.

• Always query for clarification if "intractable" is not explicitly documented but treatment resistance is implied.
• Do not use this code for headaches that are a side effect of a drug but are not described as intractable.
• Code the specific drug causing the headache using an adverse effect code (T36-T50 with 5th or 6th character 5) as an additional diagnosis.