From the Guidelines
Managing COVID-related taste loss should prioritize olfactory training, as it has shown benefit in improving smell and subsequently taste perception, according to the most recent guidelines 1. The approach to managing COVID-related taste loss involves several key strategies.
- Smell training is recommended, which can be done by sniffing four distinct scents (like lemon, rose, clove, and eucalyptus) for 20 seconds each, twice daily for at least 3 months, as this helps retrain the olfactory system, which is closely linked to taste perception 1.
- Maintaining good oral hygiene through brushing teeth, tongue, and using alcohol-free mouthwash is also important.
- Staying hydrated and consuming a varied diet with different textures and temperatures can help maximize sensory input.
- Adding herbs, spices, and acidic ingredients to food may enhance flavor perception.
- While evidence is limited, zinc supplements (25-50mg daily) and alpha-lipoic acid (600mg daily for 2-3 months) have shown some potential benefits in smell and taste disorders 1. It's essential to note that the current evidence does not strongly support the use of pharmacologic therapies like steroids, theophylline, and sodium citrate for COVID-related taste loss, as stated in the consensus statement by the clinical olfactory working group 1. The mechanism behind COVID-related taste loss is believed to involve viral damage to supporting cells around taste buds and olfactory neurons, which typically heal over time as the body repairs this damage. If taste loss persists beyond 6 months, it is recommended to consult an otolaryngologist for further evaluation.
From the Research
Covid Taste Loss Management
- Covid-19 patients often experience taste loss, with 20-85% of patients reporting this symptom 2
- The pathophysiology of Covid-19 taste loss is not fully understood, but potential mechanisms include direct damage to the olfactory and gustatory systems, as well as local inflammation 2
- Potential treatments for Covid-19 taste loss include neuroprotective, anti-inflammatory, or depolarizing agents, such as phosphodiesterase inhibitors, insulin, and corticosteroids 2
Treatment Options
- Alpha-lipoic acid has been studied as a potential treatment for Covid-19-related smell loss, but a randomized controlled trial found no significant difference between alpha-lipoic acid and placebo in improving olfactory function 3
- Zinc supplementation has been shown to decrease 30-day death, ICU admission rate, and shorten symptom duration in Covid-19 patients 4
- Long-term taste outcomes after Covid-19 have been studied, with one cross-sectional study finding no significant difference in taste function between individuals with and without a history of Covid-19 5
Mechanisms and Pathways
- The SARS-CoV-2 virus binds to the human angiotensin-converting enzyme 2 (ACE2) receptor, leading to activation of the viral surface spike protein and potential damage to the endothelium 6
- The "cytokine storm" observed in patients with severe Covid-19 contributes to the destruction of the endothelium, leading to acute respiratory distress syndrome (ARDS), multiorgan failure, and death 6
- Alpha-lipoic acid has been proposed as a potential therapeutic agent for Covid-19 due to its antioxidant properties and ability to improve endothelial function 6