Tagamet (cimetidine)

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Brand Name

Tagamet {GlaxoSmithKline}

Generic Name

cimetidine, pronounced sye-MET-i-deen


What is Tagamet?

Tagamet is a medication that will help to decrease the amount of acid produced in your stomach. Belonging to a group of medications called histamine-2 blockers, Tagamet is used to treat and prevent some types of ulcers in your stomach. Patients with symptoms of gastroesophageal reflux disease, which is also known as GERD, may also be prescribed Tagamet. Tagamet may be used to treat a rare stomach condition called Zollinger-Ellison syndrome, which is when patients produce large amounts of stomach acid. Tagamet may also be used for other purposes not listed in this medication guide.


Key Facts About Tagamet

Tagamet should not be used for an immediate relief of your heartburn symptoms. Sometimes heartburn may be confused with initial symptoms of a heart attack. You should seek emergency medical assistance if you experience chest pain or a heavy feeling, nausea, sweating, pain spreading to your arm or shoulder, or a general feeling of being ill.

Pregnancy/Breastfeeding:Tell your doctor if you are pregnant or plan to become pregnant while you are being treated with Tagamet. Tagamet is not expected to affect and unborn baby. We know that Tagamet passes into breast milk and may harm a nursing baby. You should not use Tagamet without telling your doctor if you are breast-feeding.

You may have an increased risk of developing pneumonia while taking Tagamet. . Symptoms of pneumonia include chest pain, fever, shortness of breath, and coughing up green or yellow mucus. Tell your doctor if you are concerned about pneumonia.

You may need to take Tagamet for up to 8 weeks before your ulcer heals. Continue taking this medication as your doctor has directed.

Alcohol consumption may increase your risk of damage to your stomach while you are taking Tagamet.


Before You Take Tagamet

You should not take Tagamet if you are allergic to cimetidine.

Tell your doctor if you have are taking any medications for cancer treatments, including cisapride, dofetilide, or a nitrosoureas, like carmustine. You should not take Tagamet if you are being treated with any of these medications.

Let your doctor know if you have diabetes, kidney disease or liver disease before starting treatment with Tagamet.

Before you start taking Tagamet tell your doctor if you asthma or a chronic lung disorder.

Tell your physician if you have had a bone marrow transplant or if you have a weak immune system before beginning treatment with Tagamet.

If you also take ketoconazole (Nizoral) you should take it at least 2 hours before you take Tagamet.


Tagamet Drug Interactions

Tagamet can interfere with many medications. Talk with your doctor about all the medications and supplements you take before starting any product while using Tagamet.


  • · Cisapride
  • · dofetilide
  • · thioridazine

You should inform your doctor if you are taking any of the following as these medications should be avoided in combination with Tagamet or the dose may need to be altered or monitored while using in combination.

  • Tricyclic antidepressants (amitriptyline (Elavil))
  • Beta blocker medications alone or in combination with thiazide diuretics
  • Diabetic medications of the metformin/sulfonylurea combination or metformin alone.
  • chlordiazepoxide (Librium)
  • clopidogrel (Plavix)
  • Benzodiazepines (ie: diazepam (Valium))
  • lidocaine (Xylocaine)
  • metronidazole (Flagyl)
  • nifedipine (Adalat)
  • phenytoin (Dilantin)
  • propranolol (Inderal)
  • theophylline (Elixophyllin, Theo-24, Uniphyl)
  • Warfarin (Coumadin)

Other drugs you take that are not listed may interact with Tagamet. You should tell your doctor about all of the medications you use. This includes prescription drugs, vitamins, supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.


Directions for Taking Tagamet

Take Tagamet exactly as prescribed by your doctor. Do not take Tagamet in larger or smaller amounts, or for shorter or longer than recommended. Follow the directions on your prescription label.

You may need an antacid in addition to taking Tagamet. Your doctor will recommend an antacid to help relieve your pain if needed. Do not take any antacids without talking to your doctor first. Follow your doctor’s directions about the type of antacid to use, how to use it and when to use it.

Do not break, chew or crush the Tagamet tablet, and take this medicine with a full glass of water.

Use a special dose-measuring spoon or cup to administer Tagamet liquid. Do not use a regular table spoon. If you do not have a dose-measuring device your pharmacist can give one to you.

Be aware that Tagamet may take up to 8 weeks to heal your ulcer. Do not stop taking Tagamet without talking to your doctor first.

If you smoke and take Tagamet it may take longer for your ulcer to heal. You should not smoke cigarettes while taking Tagamet.

Tagamet should be stored at room temperature, and away from both moisture and heat.

If you miss a dose of Tagamet you should attempt to take the missed dose as soon as you remember. However, if it is almost time for your next scheduled dose do not take the missed dose in addition to your regular dose.


Tagamet Side Effects

If you experience any of the following adverse effects you should stop taking Tagamet and

seek emergency medical help immediately

  • v allergic reaction including breathing difficulties, hives, and swelling of your mouth, nose or throat
  • v bleeding or bruising easily
  • v chest congestion
  • v cough
  • v feeling faint, disorientated or confused
  • v fever
  • v heart rate that is uneven, either too fast or too slow
  • v jaundice or yellowing of the skin or eyes
  • v rash (extreme)
  • v sore throat and headache with a severe blistering, peeling, and red skin rash alongside a fever
  • v trouble breathing
  • v urinating less than usual
  • v weakness


Less serious side effects

of Tagamet may include:

  • agitation
  • breast swelling or tenderness (in men)
  • constipation
  • depression
  • diarrhea
  • dizziness
  • headache
  • joint or muscle pain
  • skin rash (mild)

It should be noted that this is not a complete list of possible side effects of Tagamet. You should contact your physician for a complete list and medical advice regarding these effects.


Tagamet Description and Dosing

Tagamet is available as a tablet or in a liquid solution. The liquid solution is 300 mg (of cimetidine) per 5 mL. Tagamet tablets are available in dosages of 300 milligrams, which are light green, round, film-coated tablets imprinted with “TAGAMET SB 300”. Tagamet 400 milligram tablets are light green, oval, film-coated and imprinted with “TAGAMET SB 400”.

Dosages of Tagamet will vary based on each individual patient. Your doctor will tell you what dosage of Tagamet is right for you and your specific condition. You should follow your doctor’s instructions exactly when taking Tagamet.

If you suspect that you have overdosed with Tagamet you should seek emergency help immediately.

Ingredients in Tagamet:

Tagamet has the active ingredient cimetidine. The 300 milligram tablets also contain the inactive ingredients carnauba wax, cornstarch, FD&C blue no. 2, iron oxide, magnesium stearate, microcrystalline cellulose, Opadry Green, povidone, sodium lauryl sulfate, sodium starch glycolate and talc. The Tagamet 400 milligram tablets contain the following inactive ingredients: carnauba wax, cornstarch, FD&C blue no. 2, iron oxide, magnesium stearate, microcrystalline cellulose, Opadry Green, povidone, sodium lauryl sulfate, sodium starch glycolate and talc. The liquid form of Tagamet contains cimetidine.

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The information contained in this drug guide is intended as an educational resource only. This guide is not exhaustive and does not contain all available information about this drug.This guide is not intended as medical advice for individual conditions or treatment.

The information provided in this guide does not replace the need for the advice and services of medical professionals or the need for medical examination. Always talk to your physician or pharmacist before taking any prescription medication or over the counter drugs (including any supplements) or before making any changes to your treatment. Only your doctor, nurse or pharmacist can provide you with safe and effective advice regarding your drug treatment.

The use of the information in this guide is at your sole risk. This information is provided "AS IS" with no warranties to accuracy or timeliness.

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