Indications
Vonoprazan is used to reduce stomach acid. It is used to heal and prevent the return of erosive oesophagitis (damage to the food pipe caused by acid reflux), to relieve heartburn from gastro oesophageal reflux disease (GERD), to treat and prevent stomach and duodenal ulcers, and, together with antibiotics, to clear Helicobacter pylori infection of the stomach. Some packs are combination kits containing Vonoprazan with antibiotics for H. pylori treatment.
How It Works
Vonoprazan is a potassium competitive acid blocker (P CAB). It blocks the proton pump, the final step in the stomach cells that release acid. Unlike older acid reducers such as Omeprazole, it does not need acid to be activated, so it works quickly from the first dose and gives strong, steady acid control throughout the day and night.
Dosage and Administration
For healing erosive oesophagitis, the usual adult dose is 20 mg once a day for up to 8 weeks, followed by 10 mg once a day to keep it healed, as prescribed. For H. pylori, it is usually 20 mg twice a day with the antibiotics in the kit for 7 to 14 days, exactly as prescribed. It can be taken with or without food. Swallow the tablet whole. Complete the full H. pylori course even if you feel better.
Interactions
Because it lowers stomach acid strongly, it can reduce the absorption of medicines that need acid, such as Atazanavir, Rilpivirine, Ketoconazole, Itraconazole, Erlotinib and Iron tablets; some of these should not be taken together. Clarithromycin (often in H. pylori kits) raises Vonoprazan levels. Strong enzyme inducers such as Rifampicin or Carbamazepine lower its effect. Tell your doctor about all medicines.
Contraindications
- Allergy to Vonoprazan or any ingredient.
- Use with Atazanavir or Rilpivirine (HIV medicines).
- For combination kits: allergy to any of the included antibiotics, such as penicillin (Amoxicillin) or Clarithromycin.
Side Effects
Common effects include diarrhoea, constipation, nausea, abdominal pain or bloating, headache and rash. With H. pylori kits, taste changes and stomach upset from the antibiotics are common. Long term use may lower absorption of vitamin B12 and magnesium and may raise the risk of some gut infections.
Get urgent medical help if you have severe or bloody diarrhoea, swelling of the face or throat, difficulty breathing, a blistering or peeling rash, black tarry stools, vomiting blood, or severe abdominal pain.
Pregnancy and Lactation
There is limited information on use during pregnancy; use only if your doctor decides it is needed. Antibiotic kits for H. pylori are usually delayed until after pregnancy. Vonoprazan may pass into breast milk; ask your doctor before use while breastfeeding.
Precautions and Warnings
Tell your doctor if you have liver or kidney disease. See a doctor before treatment if you have trouble swallowing, unexplained weight loss, repeated vomiting, vomiting blood or black stools, because these may be signs of a more serious illness. Use the lowest dose for the shortest time needed. Stomach acid tests and some H. pylori tests can be affected; tell the doctor you are taking it.
Overdose
Experience is limited. Contact a doctor or hospital if too much has been taken; treatment is supportive.
Therapeutic Class
Potassium competitive acid blocker (P CAB); acid suppressant for peptic ulcer and reflux disease.
Storage
Store below 30°C in a dry place, away from light and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.