Lansoprazole (Prevacid) a proton-pump inhibitor (PPI). It treats heartburn, gastroesophageal reflux disease (GERD), and other similar conditions by lowering the amount of acid produced in the stomach. Lansoprazole (Prevacid) is available over the counter (OTC) for adults only, while providers can prescribe lansoprazole (Prevacid) for children and adults. Lansoprazole (Prevacid) is taken by mouth, typically once daily for most conditions. Although there aren't many noticeable side effects on a day-to-day basis, long-term use of lansoprazole (Prevacid) can raise certain risks like bone fractures.
For adults only:
Frequent heartburn (2 or more days a week) - OTC only
Lower the risk of duodenal ulcer caused by Helicobacter pylori (H. pylori) infection
Lower the risk of stomach ulcer due to nonsteroidal anti-inflammatory drugs (NSAID)
Other medical conditions that cause too much stomach acid (e.g., Zollinger-Ellison syndrome)
For adults and children:
Lansoprazole (Prevacid) is a proton pump inhibitor (PPI). It blocks acid from getting "pumped" into the stomach. This helps relieve heartburn and other medical conditions that cause too much stomach acid.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Incidence not known
Back or leg pains
bleeding gums
blistering, peeling, or loosening of the skin
bloody, black, or tarry stools
change in mental status
chills
clay colored stools
dark or bloody urine
difficulty with swallowing
drowsiness
fast heartbeat
general body swelling
high fever
hoarseness
indigestion
loss of appetite
lower back or side pain
mood or mental changes
muscle spasms (tetany) or twitching seizures
nosebleeds
painful or difficult urination
pains in the stomach, side, or abdomen, possibly radiating to the back
pale skin
pinpoint red spots on the skin
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
red skin lesions, often with a purple center
red, irritated eyes
seizures
sores, ulcers, or white spots on the lips or in the mouth
stomach tenderness
swelling of the feet or lower legs
swollen or painful glands
tightness in the chest
trembling
unusual tiredness or weakness
yellow eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Dizziness
headache
Rare
Bad, unusual, or unpleasant (after) taste
belching
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
change in taste
feeling of heat or warmth
flushing or redness of the skin, especially on the face and neck
mild diarrhea
mild headache
mild vomiting
stomach discomfort or upset
sweating
Incidence not known
Decrease in passing urine (dribbling)
decrease in the frequency of urination
decrease in urine volume
difficulty with speaking
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Can continue to use with antacids, such as calcium carbonate
Available as over-the-counter and lower-cost generic options
Capsules can be opened and sprinkled over soft foods (e.g., applesauce, yogurt)
Typically few to no noticeable day-to-day side effects
Takes about 3 days for the medication to fully kick in, so not the best choice for immediate heartburn relief
Might cause or worsen lupus
Long-term use might weaken bones and raise the risk of bone fracture
Typically, lansoprazole (Prevacid) is taken before your meals. If you're taking the medication twice daily, take your first dose before breakfast and your second dose before dinner. Ask your provider or pharmacist if you have questions about the best time to take lansoprazole (Prevacid).
Swallow the lansoprazole (Prevacid) pills whole. Don't chew or crush the pills. Doing so can change how the medication gets absorbed into your body.
Lansoprazole (Prevacid) capsules: If you can't swallow the capsules, you can open the capsule and sprinkle the granules inside onto one tablespoon of applesauce, cottage cheese, or yogurt. Alternatively, you can also mix the granules with 60 mL of apple or orange juice. Once mixed, swallow the mixture right away without chewing or crushing the granules. You can drink some water afterwards to make sure you've swallowed all the medication. Don't save any of the mixture for later, since the medication might not work as well anymore.
Lansoprazole (Prevacid) orally disintegrating tablets: Make sure your hands are dry before handling lansoprazole (Prevacid) tablets. Place the tablet on your tongue to let it dissolve for about a minute. You can take it with water or swallow the medication with saliva.
Lansoprazole (Prevacid) can interact with many medications. Let your provider or pharmacist know what medications you take or plan to take. These medications include over-the-counter products and supplements. Talk with your provider or pharmacist if you have any questions about interactions with this medication.
If you're ready to stop lansoprazole (Prevacid), ask your provider if they need to lower your dose slowly over time. Stopping PPIs suddenly, especially after you've been taking one regularly for a while, might cause GERD symptoms to flare up.
Over-the-counter lansoprazole (Prevacid)
Stop taking lansoprazole (Prevacid), and speak with a provider if you need this heartburn medication for more than 14 days or if you need more than one course of treatment every 4 months. You might have a more serious condition that needs more medical attention.
Get medical help right away if you experience trouble or pain swallowing, bloody vomit, bloody or black stools, heartburn with lightheadedness or sweating, shoulder pain with shortness of breath, or chest pain. These can be symptoms of serious medical conditions, such as stomach bleeding or heart attack, which need to be treated as soon as possible.
Lansoprazole (Prevacid) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Frequent episodes of heartburn can be a symptom of stomach cancer. If your heartburn gets worse or comes back after taking lansoprazole (Prevacid), let your provider know. Also contact your provider if you have poor appetite, unexplained weight loss, or weakness along with your heartburn. They can check if there are other serious medical problems going on.
Some people taking PPIs like lansoprazole (Prevacid) have had sudden kidney problems. These problems can happen at any point during treatment. Talk with your provider if you are urinating more or less than usual, feel nauseous or weak, or have a fever, rash, or joint pain. These can be symptoms of kidney problems.
Risk factors: Older people | Recent stay at a hospital or nursing home | People with a weakened immune system (e.g., HIV, cancer)
Some clinical studies showed that PPIs, such as lansoprazole (Prevacid), can raise the risk of getting a bacterial infection called Clostridioides difficile (C. diff). This infection can cause severe diarrhea. Your risk is higher if you're over 65 years old, have recently stayed at a hospital or nursing home, or have a weakened immune system. To lower your risk of C. diff diarrhea, take the lowest possible dose of lansoprazole (Prevacid) for the shortest amount of time that works well for you. If you experience severe or watery diarrhea, fever, belly pain, loss of appetite, or nausea, let your provider know right away.
Risk factors: Taking high doses of lansoprazole (Prevacid) | Taking lansoprazole (Prevacid) for longer than a year | Risk for osteoporosis
PPIs like lansoprazole (Prevacid) might raise the risk of bone fractures in the hip, wrist, or spine. Your risk is higher if you take more than one dose of lansoprazole (Prevacid) per day or if you take it for more than a year. To prevent the risk of bone fracture, take the lowest possible dose of lansoprazole (Prevacid) for the shortest amount of time for your symptoms. If you've had bone fractures before or have osteoporosis (weak bones), talk to your provider about your risk before using this medication.
PPIs, such as lansoprazole (Prevacid), have rarely caused serious skin reactions. These reactions include Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Symptoms can include fever, body aches, rash, peeling skin, painful blisters, and swelling of the face. If you notice any of these symptoms, get medical help immediately.
Some people taking PPIs like lansoprazole (Prevacid) developed new or worsening lupus, a condition where your immune system attacks your own body. Lupus symptoms can occur any time during treatment with lansoprazole (Prevacid). Some typical symptoms include joint pain or rash, but they often improve within 1 to 3 months of stopping this medication. If you experience any lupus symptoms while taking lansoprazole (Prevacid), stop the medication and contact your provider.
Risk factor: Long-term use | Taking medications that can lower magnesium levels
Using acid-lowering medications like lansoprazole (Prevacid) for a long period of time can cause your vitamin B12 levels to drop. Lansoprazole (Prevacid) lowers the amount of acid in your stomach, which is needed for vitamin B12 absorption. If you've been taking this medication for longer than 3 years, or if you have symptoms of vitamin B12 deficiency (e.g., dizziness, muscle weakness, pale skin, tiredness, tingling in arms or legs), talk to your provider.
Taking lansoprazole (Prevacid) can also lower your magnesium levels. This can happen 3 months after taking lansoprazole (Prevacid), but it's more likely after a year of treatment. Low magnesium levels can sometimes lead to other electrolyte problems. You're at risk for low magnesium levels if you take other medications that can affect electrolyte levels, such as digoxin (Lanoxin) or water pills. Your provider might check your blood during treatment with lansoprazole (Prevacid) to make sure your electrolyte levels are in the normal range. Watch for symptoms of electrolyte problems like irregular heart rate, muscle cramps, and tremors. Let your provider know right away if they occur.
Some medications can interfere with how your body gets rid of lansoprazole (Prevacid). Depending on if they boost or block how lansoprazole (Prevacid) gets removed, the medications can affect the amount of lansoprazole (Prevacid) in your body, how well it works, and the risk of side effects. For example, St. John’s Wort and rifampin (Rifadin) can lower the amount of lansoprazole (Prevacid) in your body and cause the medication to not work as well. Avoid these medications while taking lansoprazole (Prevacid).
Lansoprazole (Prevacid) can also interfere with how other medications work. lansoprazole (Prevacid) can raise the risk of methotrexate toxicity when taken together with methotrexate. Lansoprazole (Prevacid) can also raise the risk of bleeding when taken together with warfarin (Coumadin). Your provider'll monitor your blood work regularly to make sure these medications are safe for you to take.
The orally disintegrating tablets of lansoprazole (Prevacid) contain phenylalanine, a sweetener that's often added to medications. Phenylalanine is harmless to most people, but it can be dangerous to people with an inherited medical condition called phenylketonuria (PKU). Avoid using the orally disintegrating tablets if you or your child has a history of PKU. Consider using the capsule formulation, which doesn't contain phenylalanine. Talk to a provider if you're not sure which products contain phenylalanine and which products are safer options before using any formulation.
Lansoprazole (Prevacid) is available both over the counter (OTC) and by prescription. The OTC strength is 15 mg, and the prescription strengths are 15 mg and 30 mg.
The dosing for adults is listed below. Dosing for children will depend on the child’s weight, age, and the reason they're taking the medication. In general, your child's provider will determine the dosage your child needs to take.
OTC dosing (adults):
Heartburn: The typical dose is 15 mg by mouth once daily for 14 days.
Prescription dosing (adults):
Prescription-strength esomeprazole is available as capsules and orally disintegrating tablets.
Stomach or duodenal ulcer: The typical dose is 15 mg or 30 mg by mouth once daily for 4 to 8 weeks, depending on the type of ulcer.
Lower risk of stomach ulcer from NSAIDs: The typical dose is 15 mg by mouth once daily for up to 12 weeks.
H. pylori triple therapy: The typical dose is 30 mg by mouth twice daily for 10 to 14 days. It's usually taken together with amoxicillin and clarithromycin.
H. pylori dual therapy: The typical dose is 30 mg by mouth three times daily for 14 days. It's usually taken together with amoxicillin.
GERD: The typical dose is 15 mg by mouth once daily for up to 8 weeks.
Treatment of EE: The typical dose is 30 mg by mouth once daily for up to 8 weeks.
Maintenance of EE: The typical dose is 15 mg by mouth once daily.
Medical conditions that cause too much stomach acid: The typical starting dose is 60 mg by mouth once daily. The maximum dose is 90 mg twice daily.
Your dose might be different if you have liver problems.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
History of allergy to PPIs
People receiving Edurant (rilpivirine) or rilpivirine-containing medications (e.g., Complera)
For adults only:
Frequent heartburn (2 or more days a week) - OTC only
Lower the risk of duodenal ulcer caused by Helicobacter pylori (H. pylori) infection
Lower the risk of stomach ulcer due to nonsteroidal anti-inflammatory drugs (NSAID)
Other medical conditions that cause too much stomach acid (e.g., Zollinger-Ellison syndrome)
For adults and children:
Heartburn — OTC only
Lower the risk of stomach ulcer due to nonsteroidal anti-inflammatory drugs (NSAID)
Lower the risk of duodenal ulcer caused by Helicobacter pylori (H. pylori) infection
Other medical conditions that cause too much stomach acid (e.g., Zollinger-Ellison syndrome)
Heartburn — OTC only
Lower the risk of duodenal ulcer caused by Helicobacter pylori (H. pylori) infection
Other medical conditions that cause too much stomach acid (e.g., Zollinger-Ellison syndrome)
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Centers for Disease Control and Prevention. (2023). What is C. diff?
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