Understanding Cimetidine: A Comprehensive Guide

Names of Medication

In the United States, Cimetidine is best known by its brand name, Tagamet (Cimetidine).

Pharmacologic category

Cimetidine belongs to a class of drugs known as H2 blockers or H2 antagonists, which also includes medications such as Ranitidine (Zantac), Famotidine (Pepcid), and Nizatidine (Axid).

Dosing

Cimetidine is used to treat various conditions affecting the stomach and esophagus. The dosage, frequency, and length of treatment depend on the specific disease being treated.

Gastroesophageal reflux disease (GERD)

The typical dose for treating GERD is 800 mg once daily at bedtime or 400 mg twice daily, for up to 12 weeks.

Peptic ulcer disease

For peptic ulcer disease, the usual dose is 800 mg once daily at bedtime or 300 mg four times daily with meals and at bedtime for 4-6 weeks.

Zollinger-Ellison syndrome

In cases of Zollinger-Ellison syndrome, a condition where the stomach produces too much acid, the dosage can be as high as 2400 mg per day, divided into multiple doses.

Erosive esophagitis

For erosive esophagitis, the typical dose is 1600 mg per day, divided into multiple doses.

Nonerosive reflux disease

For nonerosive reflux disease, the usual dose is 800 mg once daily at bedtime or 400 mg twice daily.
Remember, it is important not to adjust the dose of your medication without first speaking with your doctor.

Dosage Forms and Strengths

Cimetidine is available in both tablet and injectable forms. Tablet strengths include 200 mg, 300 mg, 400 mg, and 800 mg. The injectable form is available as a 300 mg/2 ml solution.

Administration Instructions

Cimetidine tablets should be taken by mouth, with or without food. If your symptoms persist or worsen, consult your doctor or pharmacist.

Adverse Reactions and Side Effects

While Cimetidine is generally well tolerated, side effects can occur. Some of the most common include:

Headache (Common)

Headache is a frequently reported side effect of Cimetidine. It’s believed to be caused by the drug’s impact on various hormone levels in the body.

Dizziness (Less Common)

Some patients may experience dizziness while taking Cimetidine. This is thought to occur due to changes in blood pressure or heart rate caused by the drug.

Diarrhea (Less Common)

Diarrhea can occur as a result of changes in stomach acid levels, which can affect digestion and gut motility.

Contraindications to taking Cimetidine

Contraindications are conditions or factors that serve as a reason to withhold a certain medical treatment due to the harm it could cause to the patient. Cimetidine is contraindicated in:

Patients with known hypersensitivity to Cimetidine

Patients who have had an allergic reaction to Cimetidine should not take this medication, as it could lead to severe allergic reactions such as anaphylaxis.

Patients with severe renal impairment

Cimetidine is primarily excreted by the kidneys, so it may accumulate in patients with severe renal impairment. This could increase the risk of adverse effects.

Drug to Drug Interactions

Certain medications may interact with Cimetidine, including:
Warfarin (Coumadin)
Phenytoin (Dilantin)
Theophylline (Theo-Dur)
Diazepam (Valium)
These drugs may have their effects enhanced or reduced when taken with Cimetidine due to its impact on liver enzymes that metabolize these drugs.

Cimetidine in Pregnancy

Cimetidine is classified as a pregnancy category B drug by the FDA, which means it has not been shown to harm the fetus in animal studies but there are no adequate studies in pregnant women. Always consult with a healthcare professional before starting any medication while pregnant.

Cimetidine while Breastfeeding

Cimetidine does pass into breast milk, but it is not known to cause harmful effects to the nursing infant. However, consult your healthcare provider before using this medication while breastfeeding.

Estimated Cost of Medication

The cost of Cimetidine can vary based on location and pharmacy. However, an estimated cost for a 30-day supply of 400 mg Cimetidine tablets without insurance and utilizing a GoodRx coupon is around $20-$30. Remember, these are only estimates and prices may vary.

Brief Legal Disclaimer

This article is for informational purposes only and not intended as medical advice. Always consult a healthcare professional for diagnosis and treatment. Reliance on the information provided here is at your own risk.
Brief Legal Disclaimer: This article is for informational purposes only and not intended as medical advice. Always consult a healthcare professional for diagnosis and treatment. Reliance on the information provided here is at your own risk.