Thanks for your question on HCM.
I can understand your situation and problem.
In my opinion, your son is having
allergic reaction due to either of the following.
1. Immediate allergic reaction to
azithromycin (z pack).
2. Delayed time of allergic reaction to
amoxicillin.
He is having allergic reaction for sure.
Allergic reactions are of two kinds.
1. Immediate type of reaction occurs within minutes to hours.
2. Late (delayed) type of reaction occurs after 2-3 days.
So better to
consult dermatologist and start appropriate treatment.
Treatment of allergic drug reaction is
1. Stop the suspected drug.
2. Start antihistamines and anti allergic drugs.
3. Apply
steroid cream on affected areas.
4. Drink plenty of fluids orally.
Since all these drugs are prescribed medicines, better to consult dermatologist and start treatment accordingly.