Glaucoma secondary to drugs, unspecified eye, severe stage

This code signifies a severe stage of glaucoma that has developed as a direct consequence of drug use, affecting an unspecified eye. It indicates significant and irreversible optic nerve damage and visual field loss attributable to an iatrogenic cause.

Use this code when documentation clearly states a diagnosis of drug-induced glaucoma, the severity is explicitly noted as "severe stage," and the affected eye is not specified (e.g., "bilateral" or "unspecified"). This code is appropriate when the causal drug is known or suspected to be the primary etiology of the glaucoma.

• Ensure the medical record explicitly links the glaucoma to drug use and specifies "severe stage."
• If the specific eye (right or left) is documented, use the more specific codes (H40.61X3 or H40.62X3).
• Always code the adverse effect of the drug (T36-T50 with a 5th or 6th character of 5) as a secondary diagnosis to identify the causative agent.