A case study is presented of Lomotil toxicity in a 22-month-old following ingestion of eight to ten tablets (20-25 mg of diphenoxylate and 0.20-0.25 mg of atropine). Early symptoms are those of atropinism, followed later by dangerous central nervous system depression from the second component. Hospitalization, watchful supervision, and intelligent use of opiate antagonists are the essentials of good management.