Brief Answer:
you'd better see a doctor

Detailed Answer:
Hello,

I don't understand why you had to take azithromycin, which is an antibiotic. This is not a treatment for migraine. Were you diagnosed with an infectious disease? Azithromycin may cause gastrointestinal discomfort. Despite that, attributing the symptoms to the drug is neither easy nor safe to do without first excluding other causes.

Persistent abdominal pain and vomiting require a medical assessment, so you'd better see a doctor. If you'd like to take something to relieve the discomfort you can try a proton pump inhibitor and paracetamol, unless they're contraindicated for any reason (for example prior history of allergy to any of them). They're both relatively safe to use.

Best wishes for your speedy recovery,
Dr. Panagiotis Zografakis,
Internal Medicine Specialist

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