How did you treat it? The gastroenterologist looks into it and treats it. How long does that take?

It goes by fast. Medication plus a strict diet.

Antibiotics? Or dewormer?

Anastasiya Giardia is not treated with antibiotics.

Macmirror, Nifuratel is usually prescribed for giardiasis. Treatment lasts a week, and you'll need to re-test stool after treatment.