Do Allergy Drops Have Side Effects? What You Need to Know

Manoukian, MD, FAAAI, FACAAI
February 25, 2024
July 5, 2024

Allergies can significantly impact our daily lives, affecting our ability to enjoy the outdoors, interact with pets, and even feel comfortable in our homes. For many, the quest for effective treatment leads to the discovery of sublingual immunotherapy, commonly known as allergy drops. But with any medical treatment, understanding potential side effects is crucial. In this comprehensive guide, we’ll delve into what allergy drops are, how they work, and what side effects you might expect. We’ll also explore why HeyAllergy’s online telemedicine service could be your best bet for effective and convenient allergy care.

What Are Allergy Drops?

Allergy drops are a form of immunotherapy designed to reduce or eliminate allergic reactions by gradually desensitizing your immune system to specific allergens. These drops are placed under the tongue (sublingual) and are absorbed into the bloodstream, where they begin to work on modifying your immune response.

Unlike traditional allergy shots, allergy drops can be administered at home, making them a convenient option for those with busy schedules or a dislike of needles. They are particularly beneficial for children and individuals with needle phobias.

How Do Allergy Drops Work?

The principle behind allergy drops is similar to that of allergy shots: both aim to alter your immune system’s response to allergens. By introducing small, controlled amounts of an allergen into your system, your immune response is gradually modified. Over time, your body becomes less reactive to the allergen, reducing the severity and frequency of allergic reactions.

The process typically starts with a build-up phase, where the dosage of the allergen is gradually increased. Once the optimal dose is reached, you enter a maintenance phase, continuing the treatment to sustain the desensitization process.

Potential Side Effects of Allergy Drops

As with any medical treatment, allergy drops come with the potential for side effects. However, these are generally mild and manageable. Here’s a closer look at what you might expect:

Local Reactions

The most common side effects of allergy drops are local reactions in the mouth. These can include:

Itching or tingling under the tongue

Swelling of the mouth or lips

Throat irritation

These symptoms are usually mild and tend to diminish as your body adjusts to the treatment. Drinking water or rinsing your mouth after administering the drops can help alleviate these symptoms.

Systemic Reactions

Systemic reactions, affecting other parts of the body, are rare but possible. These can include:

Skin rashes or hives

Gastrointestinal issues like nausea or abdominal discomfort

Respiratory symptoms such as sneezing or nasal congestion

While systemic reactions are uncommon, it’s important to monitor your symptoms and report any concerns to your healthcare provider.

Severe Reactions

Severe reactions to allergy drops are extremely rare but can occur. These may include:

Anaphylaxis: A severe, life-threatening allergic reaction that requires immediate medical attention. Symptoms include difficulty breathing, swelling of the face or throat, and a rapid drop in blood pressure.

Asthma exacerbation: Worsening of asthma symptoms in individuals with asthma.

If you experience any severe reactions, discontinue use and seek emergency medical care immediately.

Minimizing Side Effects: Best Practices

To minimize the risk of side effects, follow these best practices:

1. Start Slowly: Begin with a low dose and gradually increase as directed by your healthcare provider.

2. Monitor Your Symptoms: Keep a diary of any reactions and discuss them with your provider.

3. Stay Hydrated: Drink plenty of water to help reduce local irritation.

4. Adhere to Guidelines: Follow the prescribed schedule and dosage instructions carefully.

5. Seek Professional Guidance: Consult with a healthcare provider experienced in allergy treatment, such as the specialists at HeyAllergy.

Why Choose HeyAllergy for Your Allergy Drops Treatment?

At HeyAllergy, we understand the challenges that allergies can pose and the importance of effective, convenient treatment. Our online telemedicine service offers several advantages:

Expert Care

Our team of experienced allergists and immunologists are dedicated to providing personalized care tailored to your specific needs. We take the time to understand your allergy history and develop a treatment plan that works best for you.


With HeyAllergy’s telemedicine service, you can receive expert care from the comfort of your home. No need to travel to a clinic or take time off work for appointments. Our virtual consultations make it easy to fit allergy care into your busy schedule.

Comprehensive Support

From initial consultation to ongoing follow-up, HeyAllergy provides comprehensive support throughout your treatment journey. We are here to answer your questions, address any concerns, and adjust your treatment plan as needed.

Accessible Treatment

We offer a range of allergy treatments, including allergy drops, making it easy for you to find the right solution for your needs. Our goal is to help you achieve lasting relief from your allergy symptoms.

Book an Appointment with HeyAllergy Today

Don’t let allergies control your life. Discover the benefits of allergy drops and the convenience of online care with HeyAllergy. Book an appointment today and take the first step towards a healthier, allergy-free life.

FAQ About Side Effects of Allergy Drops

Are there any immediate side effects after taking allergy drops?

The most common immediate side effect is mild oral irritation, such as itching or a tingling sensation under the tongue. This usually subsides shortly after taking the drops.

Can allergy drops cause severe allergic reactions?

Severe allergic reactions to allergy drops, like anaphylaxis, are extremely rare. However, it's important to be aware of the signs and seek immediate medical attention if they occur.

Will I experience gastrointestinal issues with allergy drops?

Some individuals may experience mild gastrointestinal symptoms like nausea or stomach discomfort, especially at the beginning of the treatment. These symptoms generally decrease with continued use.

Is it common to have a change in taste after taking allergy drops?

A change in taste or a metallic taste in the mouth immediately after taking allergy drops is possible but less common. This usually resolves quickly and is not a cause for concern.

Should I stop taking allergy drops if I experience side effects?

If you experience side effects, it's important to consult with your allergist before making any changes to your treatment. They can adjust your dosage or provide guidance on how to manage the side effects.

How can I minimize the side effects of allergy drops?

Adhering to the correct administration technique and following your allergist's instructions can help minimize side effects. Also, monitoring your body's reaction and communicating any concerns to your allergist is crucial.

How long do side effects from allergy drops last?

Most side effects are temporary and will lessen as your body adjusts to the treatment. The duration can vary, but ongoing or severe symptoms should be discussed with your allergist.