Lansoprazole belongs to the family of medications called proton pump inhibitors (PPIs). These medications slow or prevent the production of acid within the stomach.

Lansoprazole is used to treat gastric (stomach) ulcers, duodenal (intestinal) ulcers, reflux esophagitis, and gastroesophageal reflux disease (GERD). It is also used in combination with antibiotics to treat and eradicate H. pylori bacteria (a major cause of duodenal ulcers).

Lansoprazole is also used to treat gastric ulcers caused by a family of pain relievers known as nonsteroidal anti-inflammatory drugs (NSAIDs), and to reduce the risk of gastric ulcers for people who are taking NSAIDs. It is also used to treat conditions associated with the over-production of stomach acid, including Zollinger-Ellison syndrome.

For children and adolescents, lansoprazole can be used to treat GERD.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

To treat duodenal (intestinal) ulcers, the recommended adult dose of lansoprazole is 15 mg daily, before breakfast, for 2 to 4 weeks. For duodenal ulcers that return, lansoprazole may be used for up to one year.

To treat gastric (stomach) ulcers, the recommended adult dose of lansoprazole is 15 mg daily, before breakfast, for 4 to 8 weeks. The usual recommended dose to treat gastric ulcers caused by NSAIDs is 15 mg to 30 mg daily, before breakfast, for up to 8 weeks. When used to reduce the risk of gastric ulcers for people who are taking NSAIDs, the usual dose is 15 mg daily, before breakfast, for up to 12 weeks.

To treat duodenal ulcers caused by H. pylori bacteria (as confirmed by a test), the recommended dose of lansoprazole is 30 mg along with clarithromycin 500 mg and amoxicillin 1,000 mg, all taken twice daily for 7, 10, or 14 days. All of these medications should be taken before meals. This combination of medications helps kill the bacteria that can cause duodenal ulcers.

To treat GERD and associated heartburn symptoms, the recommended dose of lansoprazole is 15 mg daily before breakfast for up to 8 weeks. Doses up to 30 mg daily are sometimes prescribed for reflux esophagitis or other conditions associated with increased secretion of acid by the stomach. To prevent the return of GERD symptoms, a daily dose of 15 mg may be prescribed for up to a year.

To treat GERD in children 1 to 11 years of age, the recommended dose is 15 mg to 30 mg (depending on the child's weight) once daily for up to 12 weeks. An increase in dose may be beneficial for some children. For adolescents 12 to 17 years old who have GERD, the adult dose can be used.

When treating Zollinger-Ellison syndrome or other conditions which overproduce stomach acid, the dose of lansoprazole varies, but is often higher than the doses used to treat ulcers. Doses larger than 60 mg daily are often needed.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Lansoprazole should be taken before breakfast or, if taken twice daily, before breakfast and another meal. The medication should not be crushed or chewed. The capsules should be swallowed whole with a glass of water. People who have difficulty swallowing capsules may open the capsule and sprinkle its contents on a tablespoon of applesauce, which should then be immediately swallowed.

Lansoprazole fast dissolving tablets should not be chewed or cut. They should not be swallowed whole; they should be placed on the tongue for about one minute to allow the tablet to dissolve. Once the tablet has dissolved, the particles can be swallowed. Alternatively, for adults and children who have trouble swallowing, the tablet may be dissolved in an oral syringe with water. Speak to your pharmacist for specific directions.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

15 mg
Each pink cap-green body capsule imprinted with "15" in white ink on the body and containing white-to-off-white pellets, contains 15 mg of lansoprazole.  Nonmedicinal ingredients: D&C Yellow No. 10, FD&C Green No. 3, FD&C Red No. 3, gelatin, hydroxypropyl cellulose, hypromellose, macrogols, maize starch, magnesium carbonate, methacrylic acid-ethyl acrylate copolymer, polysorbate 80, silica colloidal anhydrous, sucrose, sugar spheres, talc, and titanium dioxide.

30 mg
Each pink cap-black body capsule imprinted with "30" in white ink on the body and containing white-to-off-white pellets, contains 30 mg of lansoprazole. Nonmedicinal ingredients: D&C Yellow No. 10, FD&C Green No. 3, FD&C Blue No. 1, gelatin, hydroxypropyl cellulose, hypromellose, macrogols, maize starch, magnesium carbonate, methacrylic acid-ethyl acrylate copolymer, polysorbate 80, silica colloidal anhydrous, sucrose, sugar spheres, talc, and titanium dioxide.

Do not take this medication if you:

• are allergic to lansoprazole or any ingredients of the medication
• are taking the medication rilpivirine

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• burping
• constipation
• diarrhea
• dizziness
• dry mouth
• flu-like symptoms
• gas
• headache
• muscle pain
• nausea
• trouble sleeping
• vomiting
• weakness

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• abdominal pain
• blood in urine
• decreased urination
• joint or muscle pain
• pain or burning while urinating
• rash on the cheeks or arms that gets worse in the sun
• sinus pain
• skin rash
• sore throat

Stop taking the medication and seek immediate medical attention if any of the following occur:

• severe diarrhea with blood or mucous in the stool
• signs of a serious allergic reaction (swelling of face or throat, hives, or difficulty breathing)
• signs of a severe skin reaction (e.g., blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.

Diarrhea: When gastric acid is decreased, the number of bacteria normally in the digestive system increases. Occasionally, this can cause serious infection in the digestive tract. If you experience severe watery or bloody diarrhea, fever, or abdominal pain while taking lansoprazole, contact your doctor as soon as possible.

Electrolyte balance: Long-term use of lansoprazole may cause the levels of electrolytes such as magnesium, calcium, and potassium in the blood to decrease. If you experience symptoms of fluid and electrolyte imbalance such as muscle pains or cramps; dry mouth; numb hands, feet, or lips; or racing heartbeat, contact your doctor as soon as possible. Your doctor may do blood tests periodically to monitor the levels of these electrolytes in your blood while you are taking this medication.

Phenylketonuria: The delayed-release tablet form of lansoprazole contains aspartame, an ingredient that cannot be broken down in the body by people who have phenylketonuria (a condition where you are lacking the enzyme needed to break down phenylalanine). People with phenylketonuria should take lansoprazole delayed-release capsules instead.

Liver function: Decreased liver function may cause lansoprazole to build up in the body. If you have reduced liver function or liver disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Methotrexate interaction: Lansoprazole, like other medications in this group, may interact with methotrexate when the two medications are used at the same time. This combination may lead to higher-than-expected amounts of methotrexate in the body and can cause serious side effects, including kidney damage, irregular heartbeat, anemia, or infection. If you take lansoprazole and are also going to receive a dose of methotrexate, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

More serious conditions of the stomach and intestines: Even if you experience improvement in acid-related symptoms, it is still possible to have serious underlying stomach problems such as stomach cancer. If you experience symptoms of a more serious condition of the stomach and intestines (e.g., trouble swallowing, unplanned weight loss, vomiting of blood or food, or black stools) while taking this medication, contact your doctor immediately.

Osteoporosis fractures: Long-term use of lansoprazole may be related to an increased risk of bone fractures in the hip, wrist, or spine, as a result of weakened bones. This risk is further increased if you are at risk of developing osteoporosis. If you have osteoporosis or have risk factors for developing osteoporosis, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Severe skin reactions: Rarely, people taking lansoprazole experience a severe skin reaction that can be life-threatening. These reactions may start as a skin rash that blisters, causes sores on the lips or eyes, or covers a large area of the body. It can develop into an exfoliating skin condition, with peeling, shedding, or scaling of the skin. If you experience any of these symptoms, or any other unusual skin reaction of the skin, contact your doctor immediately.

In rare cases, Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS syndrome) may occur. This reaction involves symptoms including fever, swollen glands, yellowing of the skin or eyes, flu-like symptoms with skin rash or blistering, or other organ involvement. These reactions are medical emergencies. Get immediate medical attention if you have symptoms of a severe allergic reaction. If you experience any unusual symptoms, contact your doctor.

Subacute cutaneous lupus erythematosus (SCLE): Lansoprazole, like other PPIs, has been rarely associated with SCLE, an autoimmune disease. If you develop any skin lesions, especially in sun-exposed skin areas, and if accompanied by muscle aches or pains, contact your doctor immediately.

Vitamin B12: Long-term use of lansoprazole may lead to vitamin B12 deficiency. If you are a vegetarian or have low vitamin B12 levels, discuss with your doctor if any special monitoring is required.

Pregnancy: There are no adequate or well-controlled studies on the use of this medication by pregnant people. This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if lansoprazole passes into breast milk. If you are breast-feeding and taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of this medication have not been established for use by children under one year old. For children 1 to 17 years old, this medication can be used to treat GERD for a maximum of 12 weeks.

There may be an interaction between lansoprazole and any of the following:

• amphetamines (e.g., dextroamphetamine, lisdexamfetamine)
• ampicillin
• apalutamide
• "azole" antifungals (e.g., fluconazole, itraconazole, ketoconazole)
• belumosudil
• bisphosphonates (e.g., alendronate, clodronate, risedronate)
• capecitabine
• cefpodoxime
• cefuroxime
• clopidogrel
• doxycycline
• fluoxetine
• fluvoxamine
• HIV protease inhibitors (e.g., atazanavir, tipranavir)
• iron salts
• ledipasvir
• lumacaftor and ivacaftor
• methotrexate
• moclobemide
• monoclonal antibodies (e.g., atezolizumab, durvalumab)
• multivitamins with minerals
• mycophenolate
• octreotide
• pioglitazone
• protein kinase inhibitors (e.g., dasatinib, nilotinib)
• rifampin
• rilpivirine
• riociguat
• rosiglitazone
• St. John's wort
• tacrolimus
• theophylline
• velpatasvir
• warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.