Can you overdose on Zyrtec?

In this article:

• Zyrtec overdose
• Factors that increase risk
• What happens
• When to see a doctor
• What to do
• How to use antihistamines safely

In this article

• Zyrtec overdose
• Factors that increase risk
• What happens
• When to see a doctor
• What to do
• How to use antihistamines safely

For many people, Zyrtec is the main part of their arsenal against allergy symptoms like sneezing, runny nose, and itchy eyes. This brand-name over-the-counter (OTC) drug contains the active ingredient cetirizine, an antihistamine. Like everything else, too much of a good thing can turn into a bad thing. While many people find relief with Zyrtec when using it correctly, others might not be aware of the potential consequences of taking too much.

Zyrtec is available in different forms, such as tablets and syrups. Most adults and children over six years old can take 10 mg once per day, providing relief for 24 hours. However, younger children might need a smaller dose. A Zyrtec overdose can be serious, depending on the person and how much was ingested. 

Continue reading to learn more about the potential risk of an overdose on Zyrtec and what to do if it ever occurs.

Can you overdose on Zyrtec? 

Yes, it’s possible to overdose on Zyrtec. Overdosing on any medication, including second-generation antihistamines like Zyrtec, can increase the risk of serious side effects. While you would need to take extremely high doses for it to be dangerous, it’s still important to be careful. However, just because a person has a higher tolerance for medications doesn’t mean they should take more than the recommended dose.

The standard dosage for Zyrtec varies by age. Adults and children over six years old generally take 10 mg once daily. For younger children, ages 2 to 6, the recommended dose is 5 mg once daily or 2.5 mg twice daily. Always follow the dosing instructions to avoid complications. 

While taking more than 10 mg per day would be considered an overdose for most people, many might not experience any apparent symptoms of an overdose. It might take three, four, or five times the normal dose for a person to experience serious side effects. However, the younger and lighter a person is, the greater the chance of severe side effects from taking one or two extra doses. 

Factors that increase the risk of overdose

Some people may be more likely to overdose on Zyrtec than others because of specific factors. These factors might include having other health problems, taking other medications at the same time, or simply not understanding the directions for the medication. 

Age

Both children and older adults can be more sensitive to how medications affect them. Children’s bodies are still growing and might handle drugs differently compared to adults. On the other hand, older adults might process medications more slowly, which can change how they react to medications. This increased sensitivity might mean a higher chance of experiencing an overdose. 

Liver or kidney problems

Liver and kidney disease can affect how the body processes and removes medications like Zyrtec. Because the liver and kidneys process Zyrtec, the levels of the drug may increase when these organs aren’t working properly. Therefore, if you have these health problems, you might be more likely to overdose on regular doses of the medicine, leading to stronger effects.

Playing “catch up”

Taking more than the recommended dose of medication can happen when you try to “catch up” after forgetting to take a dose. Not keeping track of when to take the medicine might lead to accidentally taking too much.

Use of alcohol or drugs that impair judgment 

Drinking alcohol while taking Zyrtec can make side effects worse, especially drowsiness, which is a common effect of allergy medications. Mixing alcohol with Zyrtec may affect your ability to think clearly and make decisions, which might lead you to take more medicine than needed. In some cases, alcohol may worsen allergy symptoms, making it hard to tell how much medicine you’ve actually taken.

Misunderstanding instructions

Many people don’t always read medicine labels carefully or might misunderstand the instructions on how to take medication. For example, you might be confused about how often to take the medicine or how much to use, which might cause you to take more than you should. If you’re unsure about the dosage, it’s important to ask your doctor or pharmacist for help.

Taking other OTC drugs containing cetirizine

Using multiple OTC medications that contain cetirizine may increase the risk of overdose. If you’re purchasing OTC drugs because you’re so focused on getting rid of symptoms, you might not realize that you’re combining products with the same active ingredient. It’s important to read the labels to avoid taking more cetirizine than you should. Examples of OTC medications with cetirizine might include Aller-Tec and Wal-Zyr. 

The risk of overdosing on Zyrtec isn’t just about one single factor; it’s usually a combination of several things. Recognizing how these factors interact may help you use the medication more safely.

What happens if you overdose on Zyrtec?

Despite being less sedating than first-generation antihistamines, Zyrtec‘s overdose can still cause toxic effects. Symptoms of a Zyrtec overdose may include:

• Severe drowsiness
• Restlessness or irritability (especially in children)
• Fast heart rate (tachycardia)
• Confusion
• Blurred vision
• Dry mouth
• Nausea and vomiting
• Tremors

When someone takes too much Zyrtec, the symptoms can show up in different stages, especially in children. At first, a child might seem irritable or restless and might even get a bit too excited. They might then experience more serious problems, like having seizures or experiencing hallucinations. As time goes on, the child may start to feel sleepy, and their breathing could slow down. In serious cases, this could lead to a coma.

In adults, a Zyrtec overdose might look different. You might experience fever and flushing, indicating that the body is reacting poorly. You might also notice dilated pupils, a fast heartbeat, and problems fully emptying the bladder (urinary retention), which can feel unsettling. Low blood pressure can also occur, making you feel weak or dizzy. In severe cases, you might lose consciousness and enter a life-threatening coma. 

When to see a doctor

Consult a doctor or healthcare provider for any questions or concerns you have about a potential overdose on Zyrtec. Even if symptoms seem mild, it’s better to err on the side of caution. In addition, if you experience any unusual reactions after taking Zyrtec, such as severe allergic reactions or persistent side effects, seek medical help. It’s important to discuss any concerns about dosage or interactions with other medications.

What to do in the event of a Zyrtec overdose

If you suspect a Zyrtec overdose in yourself or someone else, it can be overwhelming. However, it’s important to stay calm. Overdosing on this medication, while potentially serious, can often be managed with the right resources. 

If you suspect a Zyrtec overdose, acting quickly is key. Here are some potential steps you can follow:

• Identify symptoms: Look for signs of overdose, such as irritability, restlessness, extreme drowsiness, or unusual behavior.
• Call emergency services: Immediately call 911 if serious symptoms arise, like passing out or trouble breathing.
• Contact Poison Control Center: If the symptoms are less severe, contact the Poison Control Center helpline at 1-800-222-1222 for guidance.
• Provide information: Be prepared to give the person’s age, weight, the amount of Zyrtec taken, and the time of ingestion.
• Follow instructions: Stay on the line and follow the instructions given by emergency services or poison control.
• Do not induce vomiting: Unless instructed by a healthcare professional, do not try to make the person vomit.
• Monitor the person: Keep a close watch on the person’s condition and be ready to provide updates to medical professionals.

There are resources and people who can help you through this situation, so don’t hesitate to reach out for assistance. Remember, you’re not alone—healthcare professionals are there to provide support and guidance when needed.

How to use antihistamines safely

Several other antihistamines are available besides Zyrtec that could easily cause similar symptoms during an overdose. OTC antihistamines similar to Zyrtec might include: 

• Allegra (fexofenadine)
• Claritin (loratadine)
• Xyzal (levocetirizine)
• Aerius (desloratadine)

First-generation antihistamines are known for their sedative effects and may cause more serious side effects than second-generation antihistamines like Zyrtec. Their ability to cross the blood-brain barrier often leads to drowsiness, confusion, and impaired coordination. In addition, overdosing on these medications may result in more severe symptoms.

Examples of first-generation antihistamines include:

• Benadryl (diphenhydramine)
• Chlor-Trimeton (chlorpheniramine)
• Dimetapp (brompheniramine)
• Unisom (doxylamine)

If you’re taking a new antihistamine, you may want to take certain steps to ensure you’re safely getting the most benefit from the medication. Here are some tips you can follow:

1. Follow the prescribed dosage: Always stick to the amount recommended by your healthcare provider or the instructions on the package. Taking more than what is recommended can lead to an antihistamine overdose and serious side effects.
2. Consider the timing of doses: Some antihistamines can make you sleepy, so it’s best to take them when you can avoid activities that require full attention, like driving or using heavy machinery. If you’re using a medication that causes drowsiness, consider taking it before bedtime.
3. Discuss long-term use with a healthcare provider: If you find you need to take antihistamines regularly, talk to your healthcare provider. They can help assess your situation and suggest other treatments or changes to your routine.
4. Avoid alcohol and other sedating medications: Alcohol can increase drowsiness with antihistamines. Be careful about mixing sedating antihistamines with other medications that can also cause sleepiness.
5. Consult a healthcare provider: If you have any health conditions or are taking other medications, speak to a healthcare professional before starting an antihistamine. They can help you choose the right one and check for possible interactions.

With these steps in mind, you may be able to reduce the risk of serious side effects, including those associated with toxicity. That way, you can get allergy relief when you need it without worrying about a potential trip to the emergency room.