Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Seek emergency help for trouble breathing, swelling of the face or tongue, blue or grey lips, collapse, a seizure, severe choking, or difficulty waking.
If the wrong medicine or dose may have been given, contact your local poison control service or emergency service promptly.
Do not wait for symptoms before asking for advice.
Less urgent questions about taste, storage, measuring devices, missed doses, or mild side effects can usually be handled through routine contact with a pharmacist or prescribing healthcare professional.
And for anyone, someone who:
The article also says
Call your healthcare team before the next dose if you develop a new rash, cannot keep the medicine down, have increasing trouble swallowing, or do not understand the label.
Also call if a feeding tube becomes blocked or the medicine repeatedly leaks back out.
Every sign above is quoted from the sofidex article on Liquid medication administration. If you are not sure, err upward — it is always reasonable to be checked.