T46.1X5D Adverse effect of calcium-channel blockers, subsequent encounter

ICD-10-CM T46.1X5D: Adverse effect of calcium-channel blockers, subsequent encounter

ICD-10-CM code T46.1X5D identifies an adverse effect of calcium-channel blockers during a subsequent encounter. Calcium-channel blockers are medications used to treat conditions like hypertension and angina. High doses of these agents can produce effects such as edema, headache, flushing, tachycardia, or constipation. This code is classified under the injury or poisoning semantic type. 2 3 4

Plain-language overview

Calcium-channel blockers are medications that dilate arteries by reducing calcium flux into cells to lower blood pressure, and some formulations are approved for treating angina or cardiac dysrhythmias. High doses of dihydropyridine calcium channel blockers often cause edema, headache, flushing and tachycardia. 2

What this code represents

The ICD-10-CM code T46.1X5D has the official display label of adverse effect of calcium-channel blockers, subsequent encounter. This concept is classified under the injury or poisoning semantic type. 3 4

The official display label for T46.1X5D explicitly denotes a subsequent encounter for an adverse effect of calcium-channel blockers. The terminology sources establish the code's semantic type as injury or poisoning. 3 4

Clinical context

Calcium-channel blockers are prescribed to treat various medical conditions, including hypertension, supraventricular tachycardia, vasospasm, and migraine headaches. High doses of verapamil, a calcium-channel blocker, can cause constipation. 1 2

Documentation considerations

The official terminology for T46.1X5D specifies a subsequent encounter for an adverse effect of calcium-channel blockers. The sources do not provide specific clinical documentation rules for recording this adverse effect. 3 4

What the sources add

The clinical literature describes specific high-dose effects of calcium-channel blockers, including edema, headache, flushing, tachycardia, and constipation. The terminology sources provide the official code label and semantic type without detailing these clinical effects. 2 3 4

Clinical sources identify calcium-channel blockers as widely prescribed medications for various indications in adults and children. Terminology sources define T46.1X5D as an adverse effect of calcium-channel blockers, subsequent encounter. 1 3

Questions to verify

The supplied sources do not provide coding verification rules for confirming a subsequent encounter versus an initial encounter or overdose. The sources also do not distinguish T46.1X5D from the initial encounter code T46.1X5A. 1 3 4

Sources

1. Calcium Channel Blocker Toxicity: A Practical Approach — pmc.ncbi.nlm.nih.gov; accessed 2026-07-25.
2. Calcium Channel Blockers — pmc.ncbi.nlm.nih.gov; accessed 2026-07-25.
3. EVS Explore — evsexplore.semantics.cancer.gov; accessed 2026-07-25.
4. EVS Explore — evsexplore.semantics.cancer.gov; accessed 2026-07-25.