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Prevacid (lansoprazole, proton-pump inhibitor)

Prevacid is the brand name of the drug lansoprazole. Lansoprazole is a proton pump inhibitor which reduces the amount of acid in the stomach.



What is Prevacid used for?

It treats and prevents hyperacidity caused by peptic ulcer disease (PUD), gastroesophageal reflux disease (GERD), and Zollinger-Ellison syndrome. This includes frequent heartburn that happens two or more days per week. However, it is not used for immediate relief of heartburn symptoms.

How should I take Prevacid?

Read the directions on the packaging for complete information. Check the label and expiration date.

For oral tablets, place it on the tongue to moisten it and then swallow. You can drink water after. For patients that can’t swallow the tablet whole, it can be delivered via oral syringe or nasogastric tube (NGT). Dissolve one tablet in a syringe with an appropriate amount of water. Administer the contents of the syringe. Refill the syringe with some water again and administer the remaining contents.

For IV administration, only allow licensed healthcare professionals to inject it.

Prevacid should be taken only once daily for 14 days. Do not take more than one tablet every 24 hours. It may take up to 4 days for full effect. Allow at least 4 months to pass before you start another 14-day treatment with Prevacid.

How do I store Prevacid?

This product is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store it in the bathroom or the freezer.

There may be different brands of this drug that may have different storage needs. So, it is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush this product down the toilet or pour them into a drain unless instructed to do so. Additionally, it is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Precautions & warnings

What should I know before using Prevacid?

Prevacid is not for immediate relief of heartburn symptoms. Heartburn is often confused with the first symptoms of a heart attack. Seek emergency medical attention if you have chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, and a general ill feeling.

If you also take sucralfate, avoid taking it at the same time you take Prevacid. Sucralfate can make it harder for your body to absorb lansoprazole. Wait at least 30 minutes after taking this medicine before you take sucralfate.

If you use Prevacid for longer than 3 years, you could develop a vitamin B-12 deficiency. Talk to your doctor about how to manage this condition if you develop it.

Do not use Prevacid without the advice of a doctor if you have:

  • Trouble or pain with swallowing
  • Bloody or black stools
  • Vomit that looks like blood or coffee grounds
  • Heartburn that has lasted for over 3 months
  • Frequent chest pain, heartburn with wheezing
  • Unexplained weight loss
  • Nausea or vomiting
  • Stomach pain
  • An electrolyte imbalance or metabolic disorder

Is it safe during pregnancy or breastfeeding?

Unfortunately, there isn’t enough information about the safety of using this drug during pregnancy and breastfeeding. However, it is likely safe to take. Please always consult with your doctor to weigh the potential benefits and risks before taking any medication.

This medication is pregnancy risk category B according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk
  • B=No risk in some studies
  • C=There may be some risk
  • D=Positive evidence of risk
  • X=Contraindicated
  • N=Unknown

Side effects

What side effects can occur from Prevacid?

Like all drugs, Prevacid may have side effects. If they occur, side effects are generally mild and resolve once treatment is finished or the dose is lowered. Some reported side effects include:

  • Nausea
  • Stomach pain
  • Diarrhea
  • Constipation
  • Headache

Less common, more severe side effects may include:

  • Abnormal blood levels
  • Jaundice
  • Liver damage
  • Abnormal liver enzyme levels
  • Stevens-Johnson syndrome
  • Interstitial pneumonia
  • Nephritis
  • Rash, pruritus
  • CNS depression
  • Sleep disturbances (drowsiness, insomnia)
  • Altered cholesterol levels
  • Blurry vison
  • Edema
  • Muscle pain
  • Weakness
  • Hair loss (alopecia)

However, not everyone experiences these side effects. In addition, some people may experience other side effects. So, if you have any concerns about a side effect, please consult your doctor or pharmacist.


What drugs may interact with Prevacid?

This medication may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects.

To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs, and herbal products) and share it with your doctor and pharmacist.

Drugs with known interactions:

  • Ampicillin
  • Atazanavir
  • Clarithromycin
  • Digoxin
  • Iron-containing medicines (ferrous fumarate, ferrous gluconate, ferrous sulfate, and others)
  • Ketoconazole
  • Methotrexate
  • Mycophenolate mofetil
  • Nelfinavir
  • Tacrolimus
  • Theophylline
  • Warfarin

If you experience an adverse drug interaction, stop taking this drug and continue taking your other medication. Inform your doctor immediately to reevaluate your treatment plan. Your dose may need to be adjusted, substituted with another drug, or discontinue using the drug.

Does food or alcohol interact with Prevacid?

This drug may interact with food or alcohol by altering the way the drug works or increasing the risk for serious side effects. Do not eat or drink anything before taking this medication as it will render it less effective. It is best to take it at least 30 minutes before a meal. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with Prevacid?

This drug may interact with underlying conditions. This interaction may worsen your health condition or alter the way the drug works. Therefore, it is important to always let your doctor and pharmacist know all the health conditions you currently have, especially:

  • Liver disease
  • Hypomagnesemia


The information provided is not a substitute for any medical advice. Therefore, you should always consult with your doctor or pharmacist before using any medication.

What is the dose for an adult?

Erosive esophagitis, gastric ulcer, Zollinger-Ellison syndrome:

30 mg once daily for up to 8 weeks

Duodenal ulcer:

30 mg once daily for 4-6 weeks

Elderly Patients and Patients with Impaired Hepatic Function:

15 mg once daily.

Gastroesophageal reflux disease:

The recommended dose is 15 mg orally once a day. Therapy should be continued for up to 8 weeks.

Helicobacter pylori infection:

Triple therapy: Prevacid 30 mg is combined with 1 g of amoxicillin and 500 mg of clarithromycin given orally every 12 hours for 10 or 14 days. Most investigators recommend treatment with at least two antimicrobial agents in order to achieve eradication. Monotherapy with Prevacid is ineffective and should be avoided.

Dual therapy: Prevacid 30 mg is combined with 1 gram of amoxicillin given orally every 8 hours for 14 days. Refer to the monograph for amoxicillin and/or clarithromycin for dosing information specific to elderly or renally-impaired patients.

For Prevacid IV administration

Mix it with 0.9% sodium chloride (NaCl) solution or 5% dextrose in water and administer by IV drip twice daily.

Alternatively, dissolve it in 20 mL of 0.9% NaCl solution or 5% dextrose in water and administer slowly by IV injection twice daily.

What is the dose for a child?

Gastroesophageal reflux disease:

Short term treatment of non-erosive GERD

12 to 17 years: the recommended dose is 15 mg once daily for up to 8 weeks.

Erosive esophagitis:

1 to 11 years:

  • Less than or equal to 30 kg, the recommended dose is 15 mg once daily for up to 12 weeks.
  • Greater than 30 kg, the recommended dose is 30 mg once daily, up to 30 mg twice daily for up to 12 weeks.

12 to 17 years: the recommended dose is 30 mg once daily for up to 8 weeks.

How is Prevacid available?

Prevacid is available in the following dosage forms and strengths:

  • Fast-disintegrating tablet 15 mg, 30 mg
  • Powder for injection 30 mg vial

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to the nearest emergency room.

What should I do if I miss a dose?

If you miss a dose, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

Hello Health Group does not provide medical advice, diagnosis or treatment.


Prevacid FDT/Prevacid IV https://www.mims.com/philippines/drug/info/prevacid%20fdt-prevacid%20iv Accessed June 11, 2021

Lansoprazole https://www.mims.com/philippines/drug/info/lansoprazole Accessed June 11, 2021

Lansoprazole – Drug Summary https://www.pdr.net/drug-summary/prevacid?druglabelid=1930 Accessed June 11, 2021

Prevacid Label https://www.accessdata.fda.gov/drugsatfda_docs/label/2012/020406s078-021428s025lbl.pdf Accessed June 11, 2021

Lansoprazole https://www.nhs.uk/medicines/lansoprazole/ Accessed June 11, 2021

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Written by Stephanie Nicole Nera, RPh, PharmD Updated Jun 13, 2021