What is the guidance for anosmia (loss of smell)?

From the Guidelines

Anosmia, or the loss of smell, can be managed through several approaches, with smell training therapy being a recommended treatment for persistent anosmia, as supported by the most recent and highest quality study 1. First, if you're experiencing anosmia, consult a healthcare provider to determine the underlying cause, which could range from nasal congestion to viral infections like COVID-19, or neurological conditions. For anosmia related to nasal congestion, try saline nasal sprays or rinses to clear blockages. Steroid nasal sprays like fluticasone (Flonase) or mometasone (Nasonex) may help reduce inflammation when used as directed, typically 1-2 sprays per nostril daily. Smell training therapy is recommended for persistent anosmia, involving sniffing four distinct scents (lemon, rose, clove, and eucalyptus) for 20 seconds each, twice daily for at least 3 months. This helps retrain neural pathways involved in smell perception. Avoid exposure to irritants like cigarette smoke or strong chemicals that may worsen symptoms. Most cases of viral-related anosmia improve within weeks to months, but some may require longer recovery periods. The effectiveness of these approaches varies depending on the cause of anosmia, with inflammatory conditions often responding better to treatment than neurological damage. Some key points to consider in the management of anosmia include:

• The use of olfactory training as a recommended treatment for persistent anosmia 1
• The potential benefits and risks of pharmacologic therapies, such as steroids and theophylline, although the evidence is limited and more research is needed 1
• The importance of avoiding irritants and maintaining good overall health to support recovery from anosmia
• The need for further research to fully understand the causes and effective treatments for anosmia, particularly in the context of COVID-19 1

From the Research

Anosmia Guidance

• Anosmia, or the loss of smell, is a common symptom of COVID-19, and its treatment is still being researched 2, 3, 4, 5, 6.
• Studies have investigated various interventions for the treatment of persistent post-COVID-19 olfactory dysfunction, including olfactory training, oral corticosteroids, and topical corticosteroids 2, 3, 5, 6.
• Olfactory training is the most widely recommended treatment for smell loss, but its effectiveness in COVID-19 patients is still being evaluated 2, 3, 4.
• Some studies suggest that the combination of oral corticosteroids and olfactory training may be beneficial in helping patients with enduring dysosmia recover from olfactory loss due to COVID-19 3.
• Topical corticosteroids, such as mometasone furoate nasal spray, have also been investigated as a potential treatment for post-COVID-19 anosmia, but results are mixed 6.
• The path to effective anosmia management is still somewhat unclear, but ongoing research and clinical trials may provide more insight into the best treatment options 4, 5.

Treatment Options

• Olfactory training: a non-invasive and non-pharmacological intervention that involves repeated exposure to different odors to help recover smell function 2, 3, 4.
• Oral corticosteroids: may be beneficial in combination with olfactory training, but results are mixed and more research is needed 3, 5.
• Topical corticosteroids: such as mometasone furoate nasal spray, may offer some benefit, but results are mixed and more research is needed 6.
• Other potential treatments: including neuroprotective, anti-inflammatory, or depolarizing medications, but more research is needed to fully understand their effectiveness 4.