Hi Esther,
Great question! Adverse reactions could be swelling of the skin or lips, tingling (but as you say it may simply be stimulating and temporary), a colour change, blistering, a rash, itchiness, sneezing, feeling sick, tightness in chest, difficulty breathing, stomach cramps, dizziness. The list goes on!
When tingling on lips combines with a feeling of the lips swelling, then I certainly see it as a sign to stay away. Some plants do this at certain times and not others also.
Does that help? So no need to give up basil yet but watch out for it. 🙂