Nizatidine is used to treat ulcers of the stomach and intestines and prevent them from coming back after they have healed. This medication is also used to treat certain stomach and throat (esophagus) problems (such as erosive esophagitis, gastroesophageal reflux disease-GERD). It works by decreasing the amount of acid your stomach makes. It relieves symptoms such as cough that doesn't go away, stomach pain, heartburn, and difficulty swallowing. Nizatidine belongs to a class of drugs known as H2 blockers.

This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This drug may also be used for other stomach/intestinal problems caused by too much stomach acid.

Take this medication by mouth with or without food as directed by your doctor, usually once or twice a day. If you are taking this medication once daily, it is usually taken right before bedtime. If you are using the liquid form of this medication, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose.

The dosage and length of treatment are based on your medical condition and response to treatment. Follow your doctor's instructions carefully.

If needed, antacids may be taken along with this medication.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day. Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of side effects will increase. Continue to take this medication for the prescribed length of treatment even if you are feeling better.

Tell your doctor if your condition does not get better or if it gets worse.

Headache or diarrhea may occur. If either of these effects lasts or gets worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• nausea/vomiting that doesn't stop
• loss of appetite
• stomach/abdominal pain
• yellowing eyes/skin
• dark urine
• confusion
• breast swelling/soreness in males
• easy bruising/bleeding
• signs of infection (such as sore throat that doesn't go away, fever, chills)
• fast/pounding heartbeat
• unusual tiredness

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking nizatidine, tell your doctor or pharmacist if you are allergic to it; or to other H2 blockers (cimetidine, famotidine, ranitidine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• immune system problems
• kidney problems
• liver problems
• certain lung diseases (such as chronic obstructive pulmonary disease-COPD)
• other stomach problems (such as tumors)

Some symptoms may actually be signs of a more serious condition. Get medical help right away if you have:

• heartburn with lightheadedness/sweating/dizziness
• chest/jaw/arm/shoulder pain (especially with shortness of breath, unusual sweating)
• unexplained weight loss

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

This medication passes into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products need stomach acid so that the body can absorb them properly. Nizatidine decreases stomach acid, so it may change how well these products work. Some affected products include atazanavir, dasatinib, certain azole antifungals (such as itraconazole, ketoconazole), levoketoconazole, pazopanib, sparsentan, among others.

Do not take this medication with other products that contain nizatidine or other H2 blockers (cimetidine, famotidine, ranitidine).

This medication may interfere with certain lab tests (such as urine protein tests), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lifestyle changes such as stress reduction programs, stopping smoking, limiting alcohol, and diet changes (such as avoiding caffeine and certain spices) may help this medication work better. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.

Lab and/or medical tests (such as endoscopy, kidney function) may be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.