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H-2 Blockers

Conditions Histamine-2 Blockers treat

Heartburn
Gastro-esophageal Reflux
Ulcers

How they work

The stomach pump releases hydrocholoric acid when stimulated by histamine. An H-2 blocker prevents the histamine from stimulating the pump's release of hydrocholoric acid. This reduces the level of acidity in the stomach.

There are over-the-counter versions that can be helpfull for milder forms of heartburn and indigestion; there are also stronger perscription ones that provide higher doses that help with more severe forms of GERD.

The medication is generally taken twice a day depending on severity of symptoms.

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Side effects

Side effects vary by person. If can be avoided, long term use is not recommended.

If one is self medicating with over the counter H-2 blockers, it is important to limit intake to 2 weeks.
Cimetadine (Tagamet) seems to have the most side effects and drug interactions of all the brands. For example, Cimetadine may increase sensitivity to alcohol.
The may cimetidine can decrease the body's ability to excrete caffeine, so some may experience an increase in the 'speedy' effects of caffeine, such as heart palpitations, and insomnia.
Some report confusion or depression.
Liver toxicity
Decreased platlets

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Contraindications/ drug and food interactions

These drugs can have many side effects with other drugs; it is important to ask the pharmacist if there are any interactions with other medications, vitamins, or herbal supplements you are taking.

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