Prevacid (lansoprazole): what it treats and how to use it safely

Prevacid is a proton pump inhibitor (PPI) you’ve likely heard of for treating heartburn, acid reflux and stomach ulcers. It reduces stomach acid so irritated tissue can heal. That makes it useful for GERD, gastric and duodenal ulcers, and part of H. pylori eradication therapy.

How people usually take it: adults commonly use 15–30 mg once daily for GERD or erosive esophagitis, often for 4–8 weeks. For H. pylori, doctors may prescribe 30 mg twice daily alongside antibiotics. Doses vary with the condition, and some rare disorders need higher doses under specialist care.

Common side effects and important risks

Most people tolerate Prevacid well. Short-term side effects include headache, diarrhea, nausea, abdominal pain, constipation, and gas. Watch for less common but serious problems: low magnesium (which can cause muscle cramps or irregular heartbeat), increased risk of C. difficile infection, B12 deficiency with long-term use, and a slightly higher fracture risk when used for years.

If you notice severe stomach pain, black or bloody stools, persistent vomiting, sudden weight loss, or trouble swallowing, contact a doctor right away. Also tell your provider if you’re pregnant, breastfeeding, or have liver disease — dosing and safety may change.

Interactions, precautions, and safer use

Prevacid can interact with some medicines. Examples: it may affect blood thinners like warfarin, reduce activation of clopidogrel (though less than some other PPIs), and change levels of drugs such as methotrexate or certain antivirals. Always check with a pharmacist before starting a new drug.

Use the lowest effective dose for the shortest time that controls symptoms. Consider stepping down to an H2 blocker (like famotidine) or lifestyle changes when possible: lose excess weight, avoid late-night meals, cut trigger foods (spicy, fatty, coffee, alcohol), and raise the head of the bed if reflux wakes you at night.

Thinking about buying Prevacid online? Prescription rules vary by country. If you buy online, choose a licensed pharmacy that asks for a prescription, shows a licensed pharmacist contact, and uses secure payment and tracking. Avoid sites that sell Rx drugs without a prescription or offer suspiciously low prices — counterfeit drugs are a real danger.

When Prevacid isn’t a fit, other options include different PPIs (omeprazole, esomeprazole, pantoprazole), H2 blockers, or non-drug strategies. Talk with your doctor before switching — effectiveness and risks differ by drug and by individual health factors.

If your symptoms are new, severe, or getting worse despite treatment, get checked. Proper diagnosis (sometimes with endoscopy or tests for H. pylori) keeps treatment safe and effective.

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