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URL of this page: https://medlineplus.gov/druginfo/meds/a695020.html

Lansoprazole

pronounced as (lan soe' pra zole)

Why is this medication prescribed?

Prescription lansoprazole is used to treat the symptoms of gastroesophageal reflux disease (GERD), a condition in which backward flow of acid from the stomach causes heartburn and possible injury of the esophagus (the tube between the throat and stomach) in adults and children 1 year of age and older. Prescription lansoprazole is used to treat the damage from GERD in adults and children 1 year of age and older. Prescription lansoprazole is used to allow the esophagus to heal and prevent further damage to the esophagus in adults with GERD. Prescription lansoprazole is also used to treat ulcers (sores in the lining of the stomach or intestine), to prevent more ulcers from developing in adults whose ulcers have already healed, and to decrease the risk that adults who are taking nonsteroidal anti-inflammatory drugs (NSAIDs) will develop ulcers. Prescription lansoprazole is also used to treat conditions where the stomach produces too much acid, such as Zollinger-Ellison syndrome in adults. Prescription lansoprazole is also used in combination with other medications to treat and prevent stomach ulcers caused by a certain type of bacteria (H. pylori) in adults. Nonprescription (over-the-counter) lansoprazole is used to treat frequent heartburn (heartburn that occurs two or more days per week) in adults. Lansoprazole is in a class of medications called proton pump inhibitors. It works by decreasing the amount of acid made in the stomach.

How should this medicine be used?

Prescription lansoprazole comes as a delayed-release (releases the medication in the intestine to prevent break-down of the medication by stomach acids) capsule and as a delayed-release orally disintegrating (dissolving) tablet to take by mouth. Nonprescription lansoprazole comes as a delayed-release capsule to take by mouth. Prescription lansoprazole is usually taken once a day, before a meal. When taken in combination with other medications to eliminate H. pylori, prescription lansoprazole is taken twice a day (every 12 hours) or three times a day (every 8 hours), before a meal, for 10 to 14 days. Nonprescription lansoprazole is usually taken once a day, in the morning before eating for 14 days. If needed, additional 14-day treatments may be repeated, not more often than once every 4 months. Take lansoprazole at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take lansoprazole exactly as directed. Do not take more or less of it or take it more often or for a longer time than prescribed by your doctor or stated on the package. Tell your doctor if you have taken nonprescription lansoprazole for a longer period of time than stated on the package.

Swallow the prescription capsules whole; do not split, chew, or crush them. If you have difficulty swallowing capsules, you may open the capsule, sprinkle the granules on 1 tablespoon of applesauce, Ensure® pudding, cottage cheese, yogurt, or strained pears and swallow the mixture immediately without chewing. You can also open a capsule and pour the contents into 2 ounces (60 milliliters) of orange juice, apple juice or tomato juice, mix briefly, and swallow immediately. After you swallow the mixture, rinse the glass with some additional juice and drink immediately. Then rinse the glass with juice at least two more times and drink the juice to be sure that you wash all the medication out of the glass.

Swallow the nonprescription capsules whole with a glass of water. Do not split, chew, or crush them.

Do not break, cut or chew the orally disintegrating tablets. Place a tablet on your tongue and wait up to one minute for it to dissolve. After the tablet dissolves, swallow it with or without water. If you cannot swallow the tablet, you may place it in an oral syringe, draw up 4 mL of water for a 15 mg tablet or 10 mL of water for a 30-mg tablet, shake the syringe gently to dissolve the tablet, and squirt the contents into your mouth immediately. Then draw an additional 2 mL of water into the syringe, shake gently, and squirt that water into your mouth. Do not swallow the mixture more than 15 minutes after you dissolve the tablet.

The capsule contents and orally disintegrating tablets can both be given through a feeding tube. If you have a feeding tube, ask your doctor how you should take the medication. Follow these directions carefully.

Do not take nonprescription lansoprazole for immediate relief of heartburn symptoms. It may take 1 to 4 days for you to feel the full benefit of the medication. Call your doctor if your symptoms get worse or do not improve after 14 days or if your symptoms return sooner than 4 months after you finish your treatment. Do not take nonprescription lansoprazole for longer than 14 days or treat yourself with lansoprazole more often than once every 4 months without talking to your doctor.

Continue to take lansoprazole even if you feel well. Do not stop taking prescription lansoprazole without talking to your doctor. If your condition does not improve or gets worse, call your doctor.

Ask your doctor or pharmacist for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking lansoprazole,

  • tell your doctor and pharmacist if you are allergic to lansoprazole, dexlansoprazole (Dexilant), esomeprazole (Nexium), omeprazole (Prilosec, in Talicia, in Zegerid) pantoprazole (Protonix), rabeprazole (Aciphex), any other medications, or any of the ingredients in lansoprazole capsules or orally disintegrating tablets. Ask your doctor or pharmacist for a list of the ingredients.
  • Some medications should not be taken with lansoprazole. Other medications may cause dosing changes or extra monitoring when taken with lansoprazole. Make sure you have discussed any medications you are currently taking or plan to take before starting lansoprazole with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking lansoprazole, please get the advice of your doctor or pharmacist.
  • The following nonprescription or herbal products may interact with lansoprazole: iron supplements, St. John's wort. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking lansoprazole. Do not start any of these medications while taking lansoprazole without discussing with your healthcare provider.
  • if you are taking sucralfate (Carafate), take it at least 30 minutes after you take lansoprazole.
  • tell your doctor if you have or have ever had a low level of magnesium, calcium, potassium, or sodium in your blood; hypoparathyroidism (condition in which the body does not produce enough parathyroid hormone [PTH; a natural substance needed to control the amount of calcium in the blood]); low levels of vitamin B12 in your body; osteoporosis (a condition in which the bones become thin and weak and break easily); an autoimmune disease (condition in which the body attacks its own organs, causing swelling and loss of function) such as systemic lupus erythematosus; or liver disease.
  • if you plan to take nonprescription lansoprazole, first tell your doctor if your heartburn has lasted 3 months or longer or if you have experienced any of the following symptoms: lightheadedness, sweating, or dizziness along with your heartburn; chest pain or shoulder pain; shortness of breath or wheezing; pain that spreads to your arms, neck, or shoulders; unexplained weight loss; nausea; vomiting, especially if the vomit is bloody; stomach pain; difficulty swallowing food or pain when you swallow food; or black or bloody stools. You may have a more serious condition that cannot be treated with a nonprescription medication.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking lansoprazole, call your doctor.
  • if you are 70 years of age or older, do not take this medication for a longer period of time than recommended on the product label or by your doctor.
  • if you have phenylketonuria (PKU, an inherited condition in which a special diet must be followed to prevent damage to your brain that can cause severe intellectual disability), you should know that the orally disintegrating tablets may contain aspartame, which forms phenylalanine.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Lansoprazole may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • constipation
  • nausea
  • headache
  • dizziness
  • diarrhea
  • in men, difficulty achieving or maintaining an erection

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:

  • rash; hives; itching; swelling of the eyes, face, lips, mouth, throat, or tongue; difficulty breathing or swallowing; hoarseness
  • blistering, peeling, or bleeding skin; sores on the lips, nose, mouth, or genitals; swollen glands; shortness of breath; fever; flu-like symptoms
  • increased or decreased urination, blood in urine, fatigue, nausea, loss of appetite, fever, rash, or joint pain
  • irregular, fast, or pounding heartbeat; muscle spasms; uncontrollable shaking of a part of the body; excessive tiredness; lightheadedness; dizziness; or seizures
  • severe diarrhea with watery stools, stomach pain, or fever that does not go away
  • new or worsening joint pain; rash on cheeks or arms that is sensitive to sunlight

Lansoprazole may cause other side effects. Call your doctor if you have any unusual problems while you are taking the medication.

People who take proton pump inhibitors such as lansoprazole may be more likely to fracture their wrists, hips, or spine than people who do not take one of these medications. People who take proton pump inhibitors may also develop fundic gland polyps (a type of growth on the stomach lining). These risks are highest in people who take high doses of one of these medications or take them for 1 year or longer. Talk to your doctor about the risk of taking lansoprazole.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is up and away and out of their sight and reach. https://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain laboratory tests before and during your treatment.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking lansoprazole.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Prevacid®
  • Prevacid® SoluTab®
  • Prevacid® 24HR

Brand names of combination products

  • Prevacid® NapraPAC® (containing Lansoprazole, Naproxen)

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 11/15/2023