Not all Benadryl are the same

Many BC doctors are familiar with the antihistamine with the brand name Benadryl to contain diphenhydramine (25/50 mg), to be used up to four times daily.

Brand-name Benadryl may contain different antihistamines, and dosage may range from once daily to four times a day. Side effects (e.g., level of drowsiness) may also be different. For example, Benadryl sold in London, United Kingdom, contains cetirizine (10 mg to be used once daily). In Copenhagen, Denmark, it contains acrivastin(e) (8 mg to be used up to three times daily).

Patients should read a product’s list of ingredients rather than relying on the brand name when purchasing an antihistamine, especially outside of Canada.
—H.C. George Wong, MD

H.C. George Wong, MD, FRCPC. Not all Benadryl are the same. BCMJ, Vol. 57, No. 6, July, August, 2015, Page(s) 229 - Letters.

Above is the information needed to cite this article in your paper or presentation. The International Committee of Medical Journal Editors (ICMJE) recommends the following citation style, which is the now nearly universally accepted citation style for scientific papers:
Halpern SD, Ubel PA, Caplan AL, Marion DW, Palmer AM, Schiding JK, et al. Solid-organ transplantation in HIV-infected patients. N Engl J Med. 2002;347:284-7.

About the ICMJE and citation styles

The ICMJE is small group of editors of general medical journals who first met informally in Vancouver, British Columbia, in 1978 to establish guidelines for the format of manuscripts submitted to their journals. The group became known as the Vancouver Group. Its requirements for manuscripts, including formats for bibliographic references developed by the U.S. National Library of Medicine (NLM), were first published in 1979. The Vancouver Group expanded and evolved into the International Committee of Medical Journal Editors (ICMJE), which meets annually. The ICMJE created the Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals to help authors and editors create and distribute accurate, clear, easily accessible reports of biomedical studies.

An alternate version of ICMJE style is to additionally list the month an issue number, but since most journals use continuous pagination, the shorter form provides sufficient information to locate the reference. The NLM now lists all authors.

BCMJ standard citation style is a slight modification of the ICMJE/NLM style, as follows:

  • Only the first three authors are listed, followed by "et al."
  • There is no period after the journal name.
  • Page numbers are not abbreviated.

For more information on the ICMJE Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals, visit

BCMJ Guidelines for Authors

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