Underdosing of other antiprotozoal drugs, initial encounter

This code signifies a patient's adverse reaction or complication due to taking less than the prescribed amount of an antiprotozoal medication other than antimalarials, antiamoebics, or other specified antiprotozoals. This underdosing can lead to treatment failure, worsening of the protozoal infection, or the development of drug resistance. It indicates that the patient is currently receiving active treatment for the underdosing event.

Apply this code when a patient presents with symptoms or complications directly attributable to not taking enough of an antiprotozoal drug (e.g., for giardiasis, trichomoniasis, toxoplasmosis) and this is the first time they are being seen for this specific underdosing event. This includes situations where the patient intentionally or unintentionally took a lower dose than prescribed, or stopped the medication prematurely.

• Always assign an additional code for the specific protozoal infection that is being inadequately treated.
• Distinguish carefully between underdosing (T37.3X6-) and poisoning (T37.3X1-T37.3X4-) or adverse effect (T37.3X5-).
• The 7th character "A" indicates an initial encounter, meaning the patient is receiving active treatment for the underdosing.