What do we know about antihistamines, including cetirizine, as a treatment for COVID-19?
What do we know about antihistamines, including cetirizine, as a treatment for COVID-19?
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Antihistamines are medications people can purchase over the counter without a prescription to help improve their allergy symptoms. They are among the many medications being researched as potential treatment options for COVID-19. Few studies about the efficacy of antihistamines as a treatment for COVID-19 are complete, and there is no evidence that supports the theory that antihistamines are an effective treatment for the virus. Current research is investigating whether some antihistamine medications like cloperastine, clemastine, and Azelastine can help improve symptoms or shorten the duration of COVID-19 infections, but early research has only identified these potential medications in laboratories. That means that they have not completed testing these medications in humans, so we don't know if they have any impact. Cetirizine (an antihistamine medication also known as Zyrtec) is currently being studied with famotidine (an antihistamine and antacid medication) to see whether it can be effective in treating COVID-19, particularly in patients with very aggressive immune system responses. An early study in a pre-print journal that has not been reviewed by experts or published yet, found promising results for helping ease symptoms in hospitalized patients. The study did not have a control group to compare these patients to (which is generally part of published studies on medication) and had a small population size. Overall, there has yet to be evidence that antihistamines —including certirizine—can treat COVID-19.
Antihistamines are medications people can purchase over the counter without a prescription to help improve their allergy symptoms. They are among the many medications being researched as potential treatment options for COVID-19. Few studies about the efficacy of antihistamines as a treatment for COVID-19 are complete, and there is no evidence that supports the theory that antihistamines are an effective treatment for the virus. Current research is investigating whether some antihistamine medications like cloperastine, clemastine, and Azelastine can help improve symptoms or shorten the duration of COVID-19 infections, but early research has only identified these potential medications in laboratories. That means that they have not completed testing these medications in humans, so we don't know if they have any impact. Cetirizine (an antihistamine medication also known as Zyrtec) is currently being studied with famotidine (an antihistamine and antacid medication) to see whether it can be effective in treating COVID-19, particularly in patients with very aggressive immune system responses. An early study in a pre-print journal that has not been reviewed by experts or published yet, found promising results for helping ease symptoms in hospitalized patients. The study did not have a control group to compare these patients to (which is generally part of published studies on medication) and had a small population size. Overall, there has yet to be evidence that antihistamines —including certirizine—can treat COVID-19.
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What our experts say
Antihistamines are medications people can purchase over the counter without a prescription to help improve their allergy symptoms. They are among the many medications being researched as potential treatment options for COVID-19. Few studies about the efficacy of antihistamines as a treatment for COVID-19 are complete, and there is no evidence that supports the theory that antihistamines are an effective treatment for the virus. Current research is investigating whether some antihistamine medications like cloperastine, clemastine, and Azelastine can help improve symptoms or shorten the duration of COVID-19 infections, but early research has only identified these potential medications in laboratories. That means that they have not completed testing these medications in humans, so we don't know if they have any impact.
Cetirizine (an antihistamine medication also known as Zyrtec) is currently being studied with famotidine (an antihistamine and antacid medication) to see whether it can be effective in treating COVID-19, particularly in patients with very aggressive immune system responses. An early study in a pre-print journal that has not been reviewed by experts or published yet, found promising results for helping ease symptoms in hospitalized patients. The study did not have a control group to compare these patients to (which is generally part of published studies on medication) and had a small population size. Overall, there has yet to be evidence that antihistamines —including certirizine—can treat COVID-19.
Antihistamines are medications people can purchase over the counter without a prescription to help improve their allergy symptoms. They are among the many medications being researched as potential treatment options for COVID-19. Few studies about the efficacy of antihistamines as a treatment for COVID-19 are complete, and there is no evidence that supports the theory that antihistamines are an effective treatment for the virus. Current research is investigating whether some antihistamine medications like cloperastine, clemastine, and Azelastine can help improve symptoms or shorten the duration of COVID-19 infections, but early research has only identified these potential medications in laboratories. That means that they have not completed testing these medications in humans, so we don't know if they have any impact.
Cetirizine (an antihistamine medication also known as Zyrtec) is currently being studied with famotidine (an antihistamine and antacid medication) to see whether it can be effective in treating COVID-19, particularly in patients with very aggressive immune system responses. An early study in a pre-print journal that has not been reviewed by experts or published yet, found promising results for helping ease symptoms in hospitalized patients. The study did not have a control group to compare these patients to (which is generally part of published studies on medication) and had a small population size. Overall, there has yet to be evidence that antihistamines —including certirizine—can treat COVID-19.
Context and background
While there are no current medications or treatments that prevent or treat COVID-19, many medications, including antihistamines, are being evaluated as possible treatments. Antihistamines are medications that are often available without a prescription and may be used to treat allergies (including runny nose, hives, itchy eyes) as well as insect bites, motion sickness, and insomnia.
Histamines are released in the body when there is something harmful (like an infection or an allergen—something that someone has an allergy to), and histamines cause allergy symptoms like runny nose, itchy eyes, sneezing, and rashes. Histamines can also cause swelling of blood vessels and skin. Antihistamines block the histamine reaction and decrease these symptoms or, in some cases, make the symptoms go away entirely. Similarly, in the case of COVID-19, scientists are studying whether or not antihistamines may improve some of the COVID-19 symptoms. Using antihistamines to treat symptoms of COVID-19 is an example of repurposing medications.
While developing a new medication may be possible for some new illnesses, sometimes existing medications are evaluated as treatments for new illnesses. By repurposing medications, the side effects are already understood so gaining approval may be faster than with new medicines.
While there are no current medications or treatments that prevent or treat COVID-19, many medications, including antihistamines, are being evaluated as possible treatments. Antihistamines are medications that are often available without a prescription and may be used to treat allergies (including runny nose, hives, itchy eyes) as well as insect bites, motion sickness, and insomnia.
Histamines are released in the body when there is something harmful (like an infection or an allergen—something that someone has an allergy to), and histamines cause allergy symptoms like runny nose, itchy eyes, sneezing, and rashes. Histamines can also cause swelling of blood vessels and skin. Antihistamines block the histamine reaction and decrease these symptoms or, in some cases, make the symptoms go away entirely. Similarly, in the case of COVID-19, scientists are studying whether or not antihistamines may improve some of the COVID-19 symptoms. Using antihistamines to treat symptoms of COVID-19 is an example of repurposing medications.
While developing a new medication may be possible for some new illnesses, sometimes existing medications are evaluated as treatments for new illnesses. By repurposing medications, the side effects are already understood so gaining approval may be faster than with new medicines.
Resources
- A SARS-CoV-2 protein interaction map reveals targets for drug repurposing (Nature)
- CEBINA Identifies a Common Antihistamine Nasal Spray as a Potential Anti-COVID-19 Approach (Cision)
- Potential inhibitors against 2019-nCoV coronavirus M protease from clinically approved medicines (JGG)
- Mast cell stabilisers, leukotriene antagonists and antihistamines: A rapid review of the evidence for their use in COVID-19 (CEBM)
- Dual-Histamine Blockade with Cetirizine - Famotidine Reduces Pulmonary Symptoms in COVID-19 Patients (medRxiv)
- New COVID-19 clinical trial will utilize combination of two historically safe drugs (WLOX)
- Drug Repositioning, 2017 (Innovative Approaches in Drug Discovery)
- Antihistamines, 2020 (NHS)
- A SARS-CoV-2 protein interaction map reveals targets for drug repurposing (Nature)
- CEBINA Identifies a Common Antihistamine Nasal Spray as a Potential Anti-COVID-19 Approach (Cision)
- Potential inhibitors against 2019-nCoV coronavirus M protease from clinically approved medicines (JGG)
- Mast cell stabilisers, leukotriene antagonists and antihistamines: A rapid review of the evidence for their use in COVID-19 (CEBM)
- Dual-Histamine Blockade with Cetirizine - Famotidine Reduces Pulmonary Symptoms in COVID-19 Patients (medRxiv)
- New COVID-19 clinical trial will utilize combination of two historically safe drugs (WLOX)
- Drug Repositioning, 2017 (Innovative Approaches in Drug Discovery)
- Antihistamines, 2020 (NHS)
