Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services now if someone who may have taken Lomotil:
Elsewhere, call your local poison center or emergency service.
Routine follow-up is appropriate after emergency treatment to review recovery, diarrhea care, medication safety, and any emotional or substance-use concerns.
And for anyone, someone who:
For any suspected overdose without symptoms, contact a poison center immediately.
In the United States, Poison Help is available at 1-800-222-1222 .
Do not wait for sleepiness or breathing changes, especially after a child’s possible ingestion.
New or worsening drowsiness or breathing trouble after discharge is urgent, not a routine follow-up issue.
And for anyone, someone who:
The article also says
Give naloxone if it is available and opioid overdose is suspected.
Begin rescue breathing or cardiopulmonary resuscitation if needed and if you know how.
Place a breathing but unconscious person on their side to reduce choking risk.
Stay with them until help arrives.
Every sign above is quoted from the sofidex article on Lomotil overdose. If you are not sure, err upward — it is always reasonable to be checked.