Ozempic, one of the most popular brand names for semaglutide, is making headlines not just for its remarkable weight loss effects but also for a slew of unexpected side effects.

 

 

 

Ozempic tongue’s changing tastes

 

Systematic reviews have shown obesity affects taste perception and the brain's reward response to specific tastes, increasing cravings for sweet and fatty foods and reducing taste sensitivity due to high leptin levels.

Fathi M, Javid AZ, Mansoori A. Effects of weight change on taste function; a systematic review. Nutr J. 2023;22(1):22.

 

“GLP-1 receptor agonists are known to reduce cravings for sugary foods and even alcohol,” Jennie Stanford, MD, a family physician and obesity medicine specialist, tells MDLinx. “Recent studies demonstrate that Ozempic may also make foods taste different to people who are taking it, a phenomenon called ‘Ozempic tongue.’ Some people taking Ozempic report that sweet foods taste metallic, sour, or bitter. As this is less palatable, it discourages eating those types of foods, providing an additional avenue for weight loss.” 

 

Impacts on taste receptors

 

 

Dr. Stanford explains, “Changes in taste are considered to be an adverse effect of Ozempic treatment, just as decreased appetite is a side effect as well, and both of them are useful in achieving the desired goals of improved glycemic control and weight loss.”

The mechanism behind Ozempic-induced taste changes remains unclear. Yeily Hernandez Mato, MD, a board-certified physician at Community Health of South Florida, Inc., tells MDLinx, “We really don’t know yet what is causing this. There are theories that Ozempic alters the gene on the taste receptors of the tongue, but no theory has yet been backed up by conclusive evidence. More research is required.”

This is evident from a study presented at the Endocrine Society’s ENDO 2024 meeting. The study assessed taste sensitivity in semaglutide patients using strips with different taste concentrations over 16 weeks.

The structure of semaglutide is 94% similar to endogenous GLP-1.

Jensterle M, Ferjan S, Battelino T, et al. Does intervention with GLP-1 receptor agonist semaglutide modulate perception of sweet taste in women with obesity: study protocol of a randomized, single-blinded, placebo-controlled clinical trial. Trials. 2021;22(1):464.

The 2021 trial protocol for the aforementioned study noted that taste bud cells produce GLP-1, which sends paracrine signals to GLP-1 receptors on gustatory nerve fibres involved in sweet taste perception.

GLP-1 has the power to change taste sensitivity in women with obesity. Endocrine.org. June 01, 2024.

This could explain heightened sensitivity to sweet tastes and reduced desire for sugary foods in patients on Ozempic.

 

These findings build on previously reported experimental studies showing GLP-1 receptor agonists cause aversion to sweetness.

Jensterle M, Ferjan S, Battelino T, et al. Does intervention with GLP-1 receptor agonist semaglutide modulate perception of sweet taste in women with obesity: study protocol of a randomized, single-blinded, placebo-controlled clinical trial. Trials. 2021;22(1):464.

 

 

Other oral side effects 

 

Board-certified physician and obesity specialist Michael O. McKinney, MD, explains to MDLinx, “Besides taste modifications, other oral effects that can be noticed in patients on Ozempic are xerostomia, altered salivary composition, and in a few cases, oral ulcers or mucosal irritation.”

Dr. Hernandez Mato adds, “Because of the delayed gastric emptying, some patients can develop acid reflux, which will result in an acidic taste in the mouth stemming from more stomach acidity.”

Xerostomia and halitosis

Semaglutide affects GLP-1 receptors in the brain that govern water intake, diuretic, and natriuretic properties, and reduces renal angiotensin II levels. This can lead to diuresis, chronic diarrhoea, and nasopharyngitis, promoting xerostomia.

Loss of tongue fat

Obesity causes sarcopenia of the genioglossal muscle with increased tongue fat, contributing to obesity-associated sleep apnea. A pilot study in Diabetes Research and Clinical Practice found that semaglutide can significantly reduce this tongue fat content.

Jensterle M, Ferjan S, Vovk A, et al. Semaglutide reduces fat accumulation in the tongue: A randomized single-blind, pilot study. Diabetes Res Clin Pract. 2021;178:108935.

 

 

Counselling your patients with Ozempic tongue

 

“Changes in taste perceptions should be monitored,” Dr. Stanford warns. “Hypoglycemia can occur if patients don’t eat many carbohydrates, not liking the taste. In addition, if certain foods or food groups are excluded from the diet based on lack of palatability, nutrient deficiencies may occur.” For severe taste disturbance, she recommends using flavoured mouthwashes and toothpaste, chewing sugar-free gum, or eating sugar-free mints.

 

For oral health, as Dr. McKinney explains, “improving oral hygiene such as regular brushing and drinking enough fluids [is] the best way to reduce problems related to the mouth.” Staying hydrated throughout the day is especially beneficial for patients with xerostomia. Such patients should also be recommended to avoid caffeine and alcohol.

As Ozempic-induced delayed gastric emptying and frequent gastric reflux can cause halitosis and enamel erosion, advise patients to take their last meal of the day at least 3-4 hours before bed. Encourage them to avoid late-night snacking, eat smaller meals, and steer clear of spicy or acidic foods and smoking.