This Article Extract Full Text (PDF) Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services E-mail this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to My File Cabinet Download to citation manager Request Permissions Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Adinoff, A. Search for Related Content PubMed Articles by Adinoff, A. Social Bookmarking                         What's this?

PEDIATRICS Vol. 110 No. 2 August 2002, pp. 442-443

ALLERGY: THE UPPER AIRWAY

Cognitive and Other Adverse Effects of Diphenhydramine Use in Hospitalized Older Patients

Allen Adinoff, MD

Aurora, CO

Purpose of the Study. Diphenhydramine hydrochloride is a commonly prescribed medicine in hospitalized patients, but its adverse effects on older patients remain unclear.

Study Population and Methods. A total of 426 hospitalized medical patients aged 70 years or older were enrolled in a prospective cohort study in a university hospital. Measurements included baseline and daily assessments including Mini-Mental State Examination scores, Confusion Assessment Method ratings, direct observations for medical devices (urinary catheter or physical restraints), and blinded medical record extractions for diphenhydramine use.

Results. Of the 426 patients, 114 (27%) received diphenhydramine during hospitalization and shared similar baseline characteristics including age, sex, delirium risk, and Mini-Mental State Examination scores compared with nonexposed patients. The diphenhydramine-exposed group was at an increased risk for any delirium symptoms (relative risk [RR]: 1.7; 95% confidence interval [CI]: 1.3–2.3) and for individual delirium symptoms, including inattention (RR: 3.0; 95% CI: 1.5–5.9), disorganized speech (RR: 5.5; 95% CI: 1.0–29.8), and altered consciousness (RR: 3.1; 95% CI: 1.6–6.1). Exposed patients also had increased risk for urinary catheter placement (RR: 2.5; 95% CI: 1.0–6.0) and longer median length of stay (7 vs 6 days; P = .009). A dose-response relationship was demonstrated for most adverse outcomes. Overall, 24% of diphenhydramine doses were administered inappropriately.

Conclusions. Diphenhydramine administration in older hospitalized patients is associated with an increased risk of cognitive decline and other adverse effects with a dose-response relationship. Careful review of its use is necessary in this vulnerable population.

Reviewer’s Comments. Adverse reactions were mainly cognitive or related to anticholinergic effects. Most of the patients (2/3) received diphenhydramine as a routine sleep aid; another 20% prophylactically before blood transfusion (in the absence of a previous transfusion reaction). Neither would seem to be legitimate indications. It probably goes without saying that the elderly (and very young) are most vulnerable to medication side effects. So remember: be careful and don’t poison granny! This study also makes a strong case for the use of nonsedating antihistamines in this age group.

REFERENCES

Agostini JV, Leo-Summers LS, Inouye SK. Arch Intern Med.2001; 24 :2091 –2097

---

PEDIATRICS (ISSN 1098-4275). ©2002 by the American Academy of Pediatrics

CiteULike    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This Article Extract Full Text (PDF) Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services E-mail this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to My File Cabinet Download to citation manager Request Permissions Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Adinoff, A. Search for Related Content PubMed Articles by Adinoff, A. Social Bookmarking                         What's this?