COVID-19 Symptoms vs. Allergies
Written by Ada’s Medical Knowledge Team
- Allergies and a COVID-19 infection can have similar symptoms
- Allergy symptoms are caused by allergens, such as pollen or dust mites, while COVID is caused by a virus
- Unlike allergies, COVID symptoms will often be accompanied by a fever or a general feeling of unwell
- There are distinct tests to determine whether you have COVID or allergies
Allergies or COVID-19 may present with similar symptoms, even though the causes of both conditions are entirely different. As allergies and COVID-19 require completely different treatment strategies, it's important to know the differences in the symptoms. This way, you know when you should get tested for COVID-19 and when you should stay away from others.
What causes allergies?
Unlike COVID-19, which is caused by a virus, allergies are caused by allergens. Allergens are substances that cause a reaction of the immune system. When you come into contact with a specific allergen that you're allergic to, your immune system will treat this substance as an intruder and will react by producing antibodies called Immunoglobulin E (IgE) to fight these allergens. Because of this reaction in the body, you can get certain symptoms that may look like COVID-19 symptoms. 1
COVID-19 symptoms vs. allergies
The symptoms of COVID-19 and allergies, such as hay fever, may overlap, giving you the false impression that you've got COVID-19. On the other hand, people who know they have hay fever may also have COVID and think their symptoms are just due to their allergies. It's important to be well informed on both conditions and their symptoms so that there's less confusion on whether your runny nose is from allergies or COVID.
An infection with the coronavirus usually presents itself with a newly developed fever, a loss or change to your sense of smell or taste, an overall unwell feeling, and a continuous cough you didn't have before. People who suffer from allergies don't tend to have a fever, and most don't feel unwell.
Apart from this, allergies respond profoundly to antihistamines and nasal sprays, unlike in COVID-19.
Allergies may cause milder symptoms than COVID-19, which may also vary throughout the day, according to the amount of pollen or allergens you come into contact with.
If you have allergies, you may experience these symptoms:
- Sneezing and coughing
- A runny or blocked nose
- Watery or red eyes
- Itchy throat, eyes, mouth, nose, or ears
- Itchy skin or a raised rash
- Loss of smell
- Headache or pain around your temples and forehead
- Pain or tenderness around your cheeks, ears, eyes, or forehead
- Feeling tired
- Wheezing or breathlessness
- Swelling of the eyes, lips, mouth, or throat
If you know that you have allergies and you recognize your symptoms from previous years when there was a lot of pollen in the air, then your symptoms are probably due to your allergies. You can be even more certain if your symptoms decrease after taking antihistamines or after using a nasal spray. If you have symptoms that include a new cough or a loss of taste or smell with a fever, you should stay away from others and get tested for COVID as soon as possible. 2 3
Duration of allergies vs. COVID-19
Allergies usually last for as long as the allergen remains present. For pollen, this may be from late spring to fall, depending on which type of pollen you are allergic to. Tree pollen usually occurs first, followed by grass and weed pollen. These pollen seasons occur around the same time every year, so you can estimate when you might start experiencing allergy symptoms. The pollen season does vary depending on the temperature, rainfall, and your exact location. Other common allergens such as house dust mites, foods, animal fur, insect stings, and certain medicines can affect you all year long.
Compared to allergies, symptoms related to the coronavirus usually last a shorter duration and aren't influenced by the season. If you have a mild case of COVID, symptoms will typically last 1 to 2 weeks. More severe cases of COVID can take longer to recover from, anywhere from 4 to 12 weeks. If your COVID symptoms last more than 3 months, it may be considered long COVID. 3 4 5
Diagnosing an allergy or COVID-19
If you suspect you have COVID-19, you'll need a COVID test to confirm your diagnosis. There are 2 main types of COVID tests available:
- PCR test. A laboratory-based test that detects the genetic material of the virus in a patient sample, such as a nasal or throat swab. PCR tests are highly accurate, but it can take 24 hours or up to 5 days to get results.
- Antigen test. This rapid test can be performed at home or at a clinic, and results are often available within minutes. While convenient, antigen tests are known to be less sensitive than PCR tests and can produce false negative results.
If you believe allergies are the culprit of your symptoms, your doctor can diagnose you through a detailed medical history, physical exam, and a combination of tests. These may include: 6
- Allergy tests
- Blood tests
Treatment of an allergy vs. COVID-19
If you're experiencing allergy symptoms, there are several ways to alleviate symptoms. These include: 6
- Avoiding the thing you're allergic to when possible
- Steroid tablets
- Steroid creams
- Adrenaline auto-injectors, such as an EpiPen, for severe allergic reactions
- Desensitization therapy (immunotherapy), which involves gradually exposing you to the allergen over time for your body to get used to it
If you're infected with COVID your possible treatment depends on your symptoms. Read Ada's article about COVID treatments to find out more.
When experiencing symptoms like a runny nose, a headache, or a cough, you may wonder whether it’s allergies or COVID. Although some symptoms may be the same, there are some differences such as a fever and feeling unwell which may indicate a COVID infection. If you are unsure, get tested and stay away from others until you have your test results.
Q: Do people with allergies have better immune systems to fight COVID?
A: Limited studies found a lower risk of developing COVID in people with food allergies.
Q: Can I take allergy medicine with COVID?
A: Yes. Doctors recommend that patients continue to take their allergy medication so allergy symptoms don’t worsen, which might compound the symptoms of COVID.
Q: Are allergies worse after COVID?
A: There is currently limited research on the specific relationship between COVID-19 and allergies, but some people have reported experiencing a worsening of their allergy symptoms after contracting COVID-19.
Q: Are people with allergies more susceptible to severe COVID symptoms?
A: No. The CDC lists many groups at a higher risk for severe COVID, but people with allergies are not included.
Q: Does COVID give you allergies?
A: There’s currently no evidence that COVID causes allergies. However, the medical community is still learning about COVID as the pandemic evolves and new variants emerge.
Q: Does the COVID vaccine cause allergic reactions?
A: Yes, like any other vaccine or medication, COVID-19 vaccines can cause side effects, including allergic reactions, although these are rare. The benefits of getting vaccinated against COVID-19 far outweigh the risks of any potential side effects.
Dougherty J. et al. (2021). Allergy. Accessed on 16 August 2022.
NHS (2022). Don’t confuse hay fever with coronavirus, warns Leeds GP. Accessed on 16 August 2022.
NHS (2022). Allergies. Accessed on 16 August 2022.
Met Office (2022). When is hay fever season in the UK?. Accessed on 16 August 2022.
NHS (2021). Hay fever. Accessed on 16 August 2022.
NHS (2022). Allergies . Accessed on 25 January 2023.