AAAAI Ask the Expert
ANTIHISTAMINES AND WEIGHT GAIN
It has long been known that the administration of antihistamines can cause weight gain. In fact, one antihistamine, cyproheptadine, has been used for this purpose. There are many postulations as to why this occurs. One reason, which may be the most reasonable, is that histamine is known to reduce the appetite, and antihistamines, therefore, counteract this effect.
In a recent NHANES survey, antihistamine use was associated with obesity, and a study in the journal “Obesity,” (see abstract copied below) confirmed this and analyzed the use of over-the-counter antihistamines and their effect on weight gain. They found, as in the NHANES survey, that the use of over-the-counter antihistamines, including both fexofenadine and cetirizine, was associated with obesity.
Unfortunately, we know more about this association and the potential underlying reasons for it than we do about which antihistamines may be less likely to produce this effect. I know of no study comparing the effects of available antihistamines on weight gain and could find none on a literature search. Therefore, although it is not unlikely that some antihistamines may be more potent than others in this regard, the effect appears to be more class-related rather than drug-specific.
But because we have no available information on relative potency of antihistamines regarding their effect on weight gain, there is, to my knowledge, no information available to assist you in selecting a specific antihistamine that might be helpful and not produce this side effect. Therefore the only strategy available to you, if you wish to continue to use antihistamines, is to employ various agents via “trial and error.”
The other strategy of course would be to use alternative agents to supplement or replace antihistamine use. A thorough discussion of these drugs are available in two articles.
1.Morgan M and Khan DA. Annals of Allergy, Asthma, and Immunology 2008; 100:403-411.
2.Morgan M and Khan DA. Annals of Allergy, Asthma, and Immunology 2008; 100:51-526.
In summary, to my knowledge, there is no specific antihistamine which will not potentially cause the well-documented side effect of weight gain with regular use, and therefore the only alternative for you is to try different antihistamines in a “trial and error” fashion, or to supplement or substitute the use of antihistamines with alternative therapies. References and abstracts of references are copied below should you wish to read further about the issue of antihistamines and weight gain.
Thank you again for your inquiry and we hope this response is helpful to you.
Obesity
Volume 18, Issue 12, pages 2398–2400, December 2010
Abstract
The incidence of obesity in the United States has reached epidemic proportions. Previous research has shown several medications exert noticeable effects on body-weight regulation.
Histamine-1 (H1) receptor blockers commonly used to alleviate allergy symptoms are known to report weight gain as a possible side effect. Therefore, we investigated the association between prescription H1 antihistamine use and obesity in adults using data from the 2005–2006 National Health and Nutrition Examination Survey (NHANES).
Adults taking prescription H1 antihistamines were matched by age and gender with controls and compared on the basis of body measurements, plasma glucose, insulin concentrations, and lipid levels. Prescription H1 antihistamine users had a significantly higher weight, waist circumference, and insulin concentration than matched controls. The odds ratio (OR) for being overweight was increased in prescription H1 antihistamine users. H1 antihistamine use may contribute to the increased prevalence of obesity and the metabolic syndrome in adults given these medications are also commonly used as over-the-counter remedies.
Expert Opin Pharmacother. 2012 Dec;13(18):2613-24. doi: 10.1517/14656566.2012.742887. Epub 2012 Nov 10.
Potential benefits of cyproheptadine in HIV-positive patients under treatment with antiretroviral drugs including efavirenz.
Dabaghzadeh F, Khalili H, Ghaeli P, Dashti-Khavidaki S.
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