My medicines before endoscopy
Content date: 14 November 2026
A practical guide to medicines that often continue and those needing an individual plan. Review your full medicine list with the endoscopy team at least one week before the appointment, and earlier when a longer interruption is needed.
Your next step
Send a full medicine list, including supplements, and ask for a written plan before starting preparation.
Get urgent help: Severe weakness, fainting, significant bleeding, severe breathing difficulty or symptoms of very low glucose require prompt medical help. Do not wait for a message reply.
Medicines that can often continue
- Examples include certain blood-pressure medicines such as amlodipine or bisoprolol, levothyroxine for the thyroid, and epilepsy medicines such as levetiracetam. Bring your asthma inhalers. These examples are not permission to continue every heart or blood-pressure medicine; follow the approved plan.
- Do not stop epilepsy medicines, long-term steroids or transplant medicines yourself. The team must arrange dose times or an alternative if swallowing or absorption will be a problem. A permitted tablet is usually taken with a small sip of water. If it is due after the drinking cutoff, obtain specific instructions rather than skipping it or drinking a full glass.
- Bowel cleansing can reduce the absorption of oral medicines. Ask the pharmacist to specify the gap from your actual preparation product; do not assume the same interval suits every medicine. Some antibiotics, iron and digoxin need particular spacing with magnesium-containing preparations.
Medicines that need an adjustment plan
- Insulin and other diabetes medicines need a plan for fasting, glucose checks and restarting treatment. Never stop all insulin yourself. SGLT2 medicines such as dapagliflozin and empagliflozin usually require a 3-day interruption before planned procedures; ertugliflozin requires 4 days. The team must confirm the plan, including for people taking them for heart or kidney disease.
- With SGLT2 medicines, vomiting or abdominal pain with rapid or deep breathing or marked weakness can signal ketoacidosis even without very high glucose. Seek emergency assessment and tell the team the medicine name and last dose; do not wait for a message reply.
- GLP-1 medicines such as semaglutide and tirzepatide need individual assessment, especially during dose escalation or with nausea, vomiting or persistent fullness. They are not automatically stopped for everyone. Ask whether your plan requires a liquid-only diet for 24 hours before the procedure. If so, it replaces the standard dinner allowance; follow the unit’s permitted fluids and cutoff. A longer fast alone may not reliably empty the stomach.
- Water tablets such as furosemide, some blood-pressure medicines such as ramipril or losartan, lithium and anti-inflammatory painkillers need review because bowel preparation can affect hydration, kidneys or salts. Do not stop important heart-failure treatment yourself.
- Before colonoscopy, the team may ask you to stop oral iron about 5–7 days beforehand. Anti-diarrhea medicines and fiber supplements may also need temporary interruption. The exact plan depends on the product and reason for treatment.
Acid medicines and H. pylori testing
- PPIs, such as omeprazole, esomeprazole and pantoprazole, can make H. pylori harder to detect on biopsy histology or a rapid urease test, as well as on a breath or stool antigen test. A result may be negative even though infection is present.
- For planned H. pylori testing, the usual preparation is 14 days off PPIs and 4 weeks without antibiotics or bismuth, if clinically safe and approved by the doctor. Do not stop essential treatment or interrupt an antibiotic course yourself; arrange testing around the treatment plan. Acid blockers such as vonoprazan also need review.
- PPIs do not need to be stopped before every gastroscopy. They may be needed for an ulcer, severe esophagitis or bleeding prevention. The doctor may request a different interruption when diagnosing reflux or eosinophilic esophagitis. Do not delay urgent endoscopy to complete a washout period.
- If H. pylori testing is negative while you are taking these medicines, a repeat breath or stool test after the appropriate interval may be needed. A negative result alone may not exclude infection. Ask about temporary symptom relief and follow the laboratory’s instructions.
Blood thinners: do not stop them on your own
- Tell the team about aspirin, clopidogrel, ticagrelor, warfarin, apixaban, rivaroxaban, dabigatran and any similar medicines. Review the plan jointly with the prescribing clinician and gastroenterologist; involve the cardiology or anticoagulation team when needed.
- A diagnostic examination with small biopsies has a different bleeding risk from removing a polyp or another therapeutic procedure. The plan also depends on kidney function and clotting risk, especially a recent heart stent, a mechanical valve or a recent clot. Low-dose aspirin is usually continued for most endoscopic procedures.
- If interruption is appropriate, obtain the exact last dose and restart time in writing. There is no single stopping period for all blood thinners. Do not replace tablets with injections yourself; bridging is only used for selected patients.
What to confirm before preparation starts
- For every affected medicine, record: name and dose; continue or pause; last dose; any permitted dose with a sip of water; and restart date/time. Keep the plan from the hospital performing your procedure.
- If instructions conflict, you vomit an important medicine, or you have taken a dose you were told to pause, contact the endoscopy unit. Do not double or repeat a dose yourself. Tell the team exactly what you took and when.
If glucose falls while fasting
- Monitor glucose according to your plan and carry your low-glucose treatment. If it falls below 70 mg/dL (3.9 mmol/L), and you are alert and can swallow safely, treat it immediately even while fasting: take 15 g of fast-acting carbohydrate, such as the labeled amount of glucose tablets, and recheck after 15 minutes. Repeat if glucose remains low.
- Tell the endoscopy unit what you took and when; the procedure may need rescheduling. Do not delay treatment to preserve fasting. If unconscious, having a seizure or unable to swallow, give nothing by mouth; call an ambulance and use prescribed glucagon if a trained companion is available.
When to get help
Severe weakness, fainting, significant bleeding, severe breathing difficulty or symptoms of very low glucose require prompt medical help. Do not wait for a message reply.
Contact the endoscopy unit early if any medicine, fasting or restart instruction is unclear.
Related guides
Gastroscopy preparation checklist
Acid medicines: proton pump inhibitors (PPIs)
Safe use of blood thinners (anticoagulants)
Anti-rejection medicines after liver transplantation: a practical guide
Sources
ASGE: bowel preparation and regular medicines
BSG/AUGIS 2026: upper endoscopy best practice
Saudi H. pylori Working Group recommendations
ACG 2024: H. pylori testing and treatment
BSG/ESGE: antiplatelets and anticoagulants before endoscopy
NHS: essential medicines on the day of endoscopy
NHS: medicines requiring individual preparation instructions
Picolax/Picoprep: manufacturer medicine-interaction information
ACG: diagnostic endoscopy for reflux
ASGE: Diabetes and weight-management medicines before endoscopy 2025
Multisociety recommendations: Individualizing the GLP-1 plan