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Diphenhydramine hydrochloride vs Promethazine hydrochloride

National NHS prescribing compared (Prescription Cost Analysis)
Data updated March 2026

Promethazine hydrochloride was dispensed 105.7× as often as Diphenhydramine hydrochloride in March 2026 — 252,174 items versus 2,386 in England.

2,386items

Diphenhydramine hydrochloride · March 2026

NHSBSA Prescription Cost Analysis

252,174items

Promethazine hydrochloride · March 2026

NHSBSA Prescription Cost Analysis

Figure 1. Diphenhydramine hydrochloride versus Promethazine hydrochloride: national items dispensed by month

▬ Diphenhydramine hydrochloride   ·   ╌ Promethazine hydrochloride

Promethazine hyd… 2,386

Source: NHSBSA Prescription Cost Analysis, to March 2026

Diphenhydramine hydrochloride versus Promethazine hydrochloride, March 2026
Measure Diphenhydramine hydrochloride Promethazine hydrochloride
Items, March 2026 2,386 252,174
Items, last 12 months 28,945 2,895,697
Net ingredient cost, March 2026 £12,041 £466,476

See the full profile for Diphenhydramine hydrochloride or Promethazine hydrochloride.