Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
In other countries, contact the local poison information service or emergency medical service.
Call emergency services now if the person has:
Start cardiopulmonary resuscitation if they are not breathing normally and follow emergency-service instructions.
And for anyone, someone who:
Get poison advice immediately after any suspected foxglove ingestion.
Do not wait for symptoms.
In the United States, call Poison Control at 1-800-222-1222 or use its online service.
New fainting, breathing difficulty, or an irregular heartbeat is not a routine follow-up issue and needs urgent assessment.
Routine medical follow-up is appropriate after hospital treatment if the discharge team recommends repeat heart or kidney checks.
The article also says
If the person is unconscious but breathing, place them on their side if you can do so safely.
Do not put anything in their mouth.
For plant material in the mouth, remove any remaining pieces without causing choking.
For skin exposure, wash with soap and water.
Eye exposure should be rinsed gently with clean water.
Contact a poison service if irritation continues or if any material may have been swallowed.
Every sign above is quoted from the sofidex article on Foxglove poisoning. If you are not sure, err upward — it is always reasonable to be checked.