Acidity during antibiotic treatment: what to do

Nausea, indigestion, abdominal discomfort, or diarrhoea can begin during a course. Do not stop, skip, double, or alter doses on your own; check the medicine instructions and contact a pharmacist or prescriber when side effects are troublesome.

Some antibiotics irritate the stomach or food pipe, while others alter the usual intestinal bacteria and lead to nausea, loose stools, bloating, or cramps. A tablet that lodges in the food pipe can cause painful burning, particularly when swallowed with too little water or immediately before lying down.

The infection itself, reduced appetite, irregular meals, and other medicines may contribute. Helicobacter pylori infection is treated with a specific combination of antibiotics and acid suppression; digestive symptoms during that regimen do not show on their own whether treatment is working.

Follow the pharmacy label because food instructions differ between antibiotics. If the label permits food, a simple meal may reduce stomach upset. Swallow tablets with enough water while upright, and do not lie down straight away. Choose smaller meals and avoid personal reflux triggers until the course is finished.

Ask a pharmacist before adding an antacid, acid reducer, probiotic, or supplement. Antacids and mineral products can reduce absorption of certain antibiotics when taken too close together, so spacing depends on the exact products. If a dose is vomited or missed, use the product leaflet or seek advice instead of automatically repeating it.

Call emergency services for difficulty breathing, swelling of the lips, tongue, face, or throat, collapse, or a rapidly spreading rash with blistering or peeling skin. These may signal a serious medicine reaction.

Contact a clinician promptly for severe or persistent diarrhoea, blood or mucus in stool, intense abdominal pain, repeated vomiting, yellow skin or eyes, dark urine, painful swallowing, or burning chest pain after each dose. Also get advice when side effects prevent you from completing treatment; the prescriber can decide whether the antibiotic or its formulation should change.

Confirm whether your antibiotic should be taken with food, how it should be separated from antacids or supplements, and what to do after a missed or vomited dose. Ask whether another medicine you take could be worsening acidity and which symptom would require changing treatment rather than waiting for the course to end.