Headache famotidine

Famotidine is a histamine H2 receptor antagonist. It does not affect drug metabolism and it has been claimed to be free of the antiandrogenic effect of cimetidine however in one woman who accidentally took double doses of the drug for some months it did cause hyperprolactinemia and breast engorgement (SEDA-18, 372). In other ways it bears a very close resemblance to cimetidine for example, headache and confusion with intravenous use are reported, as are thrombocytopenia and pancytopenia (SEDA-15, 395). 

A 46-year-old woman is prescribed doxycycline for a diagnosis of community-acquired pneumonia. Her PMH is significant for iron-deficiency anemia, peptic ulcer disease, HTN, a recent DVT, and headaches. Her current medications include ferrous sulfate, ibuprofen, enalapril, acetaminophen, famotidine, and warfarin. Which of her following medications is most likely to result in decreased levels of doxycycline ... 

A Famotidine, as well as some of the other antisecretory agents, can lead to headaches, dizziness, and other CNS side effects. This is particularly true in older patients or in those with compromised renal elimination. 

Cimetidine (Tagamet) Ranitidine (Zantac) Famotidine (Pepcid) Nizatidine (Axid) H2 Receptor Antagonist Duodenal/gastric ulcer, hypersecretion of acid. Well tolerated. Diarrhea, dizziness, headache. 

General side effects The most frequent side effects reported by patients receiving 40 mg of famotidine in clinical trials, with an incidence of over 1% were headache (4.7%), diarrhoea (1.7%), dizziness (1.3%) and constipation (1.2%). However, the incidence of these reported side effects was similar between famotidine and placebo (http //www.acc essdata.fda.gov/drugsatfda docs/anda/2001/75311 Famotidine Pmtlbl.pdf ). 

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