Can you juice vegetables and some fruit while on antibiotics(amoxicillin in particular) ?

When taking any prescription drug you should ask the pharmacist about interactions with food or other drugs.

The verb "to juice" refers to the extraction of liquids from fruits or veggies. Your question clearly asks about drinking the juices. You really should learn to say what you mean instead of just running the thoughts together in random disorder.

Any abdominal pain should be treated with magnesium as a precaution. Magnesium strengthens muscles, calms nerves, stops cramps, and fights infections. Get epsom salt. It is cheap, five bux for a year's supply. Put a dose in a glass with water to cover and stir until it dissolves. Fill the glass with lemonade and drink it. You can take it without the lemonade but you won't like the taste. Milk of magnesia is more expensive but nicer tasting and gentler laxative action. Your choice.