Zyrtec Makes My Kid Crazy

Zyrtec Makes My Kid Crazy


For most parents, Zyrtec has been a dependable soldier in the battle against their kids’ allergies. But what happens when this commonly used allergy medication seems to trigger unusual behavior changes in your sweet little boy or girl? Let’s delve deeper into this intriguing concern.

Understanding Zyrtec: A Common Allergy Medication

Zyrtec, a well-known name in allergy medications, is widely used to combat a range of allergy symptoms, such as runny nose, watery eyes, and itchiness caused by allergic reactions. But like all drugs, it’s not without its side effects.

The Role of Zyrtec in Allergy Relief

As an antihistamine, Zyrtec works by blocking histamine, a substance in the body that causes allergic symptoms. Whether it’s in the form of oral syrup, chewable tabs, or over-the-counter pills, this medication has provided significant relief for many during the allergy season.

Common Side Effects of Allergy Medications

All allergy meds, including Zyrtec, come with potential side effects. The most common ones include drowsiness, dry mouth, and occasionally, nausea. These side effects often dissipate as the body adjusts to the new med.

Children’s Zyrtec Side Effects: Common, Severe, Long Term

Zyrtec, a popular allergy medication, is commonly used in children to alleviate bothersome symptoms of allergies. However, as with any medication, it comes with a set of potential side effects. It’s important for parents to be aware of these side effects, both common and severe, as well as those that could manifest over the long term.

Common Side Effects of Children’s Zyrtec

As an antihistamine, Zyrtec is designed to reduce allergy symptoms, but it can also cause some side effects. The most common side effects include drowsiness, fatigue, and dry mouth. These are usually mild and often disappear as your child’s body adjusts to the medication. However, if these side effects persist or worsen, it’s essential to consult with your child’s doctor.

In some children, Zyrtec may also cause stomach discomfort or nausea. Remember, each child may respond differently to the same medication. While one child may not experience any side effects, another may experience several.

Severe Side Effects of Children’s Zyrtec

While severe side effects are less common, they can occur. These might include allergic reactions to the medication, such as rash, itching, swelling, severe dizziness, or trouble breathing. If any of these severe side effects occur, you should seek immediate medical attention.

It’s also worth noting the reports of behavioral changes in some children taking Zyrtec. This includes unusual mood swings, irritability, and hyperactivity.

While these behavioral changes are not listed as a common side effect, the number of parental reports suggests that this is an area requiring further research.

Long-Term Side Effects of Children’s Zyrtec

As of now, there are no well-documented long-term side effects of using Zyrtec in children. The medication is not typically used for prolonged periods except in cases of chronic allergies. Even in such instances, your healthcare provider will regularly monitor your child’s health.

However, there have been anecdotal reports of withdrawal symptoms after discontinuing Zyrtec, such as intense itching. These reports are not yet backed by extensive scientific research but are worth noting.

Monitoring Your Child’s Response to Zyrtec

It’s crucial to monitor your child’s response after starting any new medication, including Zyrtec. If you notice side effects or behavior changes, it’s important to report them to your child’s healthcare provider. The doctor may adjust the dosage or switch to other allergy medications if needed.

Also, consider keeping a journal of your child’s behavior, mood, and physical symptoms while they are taking the medication. This can be a helpful report for the doctor to understand the potential side effects and their impact on your child.

In conclusion, while Zyrtec is a common choice for managing children’s seasonal allergies, it’s essential to be aware of the potential side effects and to communicate openly with your child’s healthcare provider to ensure the best health outcomes for your child.

The Unexpected Side of Zyrtec: Behavioral Issues

Although not as common, some parents report behavioral changes in their children after taking Zyrtec. This completely different child can be quite a shocker, especially when your normally well-behaved kid starts showing signs of bad behavior.

Case Studies: When Zyrtec Makes Kids Act Differently

Several anecdotal stories online share the same symptoms – a child who was once their normal self suddenly becomes unruly, irritable, or overly emotional after taking Zyrtec. This unusual behavior can be alarming for parents who expect allergy relief, not a complete personality change.

Unusual Behavior in Children Taking Zyrtec

While such behavioral issues are not listed as common side effects, the sheer number of similar reports from parents cannot be ignored. Some children experience such severe changes that their parents decide to stop the medication altogether.

The Science Behind The Behavior Change

Though not fully understood, there are hypotheses that suggest how Zyrtec could impact behavior. One theory revolves around the drug’s interaction with the central nervous system.

Zyrtec and the Central Nervous System

Zyrtec, like other antihistamines, can cross the blood-brain barrier, a highly selective border that protects the central nervous system. This penetration could potentially affect brain function, leading to changes in behavior. However, peer-reviewed studies confirming this theory are still scarce.

The Role of the Blood-Brain Barrier

The blood-brain barrier serves as a defense mechanism to prevent potentially harmful substances from entering the brain. When drugs like Zyrtec cross this barrier, they can interact with the brain, potentially causing effects like drowsiness, and in some cases, behavioral changes.

Treatment and Management of Behavioural Changes from Zyrtec

In addition to physical symptoms, some children may experience unexpected side effects like behavioral changes when taking Zyrtec. These might include unusual mood swings, irritability, and hyperactivity. If you notice such behavioral issues in your child, it’s important to take steps toward proper management and treatment.

Consulting Your Child’s Doctor

At the first sign of any unusual behavior or mood changes in your child after starting Zyrtec, consult your child’s healthcare provider. They can help assess whether these changes are linked to the medication or if there might be other underlying causes.

Monitoring Behavior and Side Effects

Keep track of any changes in your child’s behavior or mood. A helpful report might include the time of day the behavior occurs, its frequency, and any possible triggers. This could provide valuable information to your child’s doctor.

Considering Dosage Adjustment or Medication Change

If the doctor confirms that the behavior changes are likely due to Zyrtec, they might adjust the dosage or switch your child to a different allergy medication. It’s important not to make these changes without consulting your child’s doctor first.

Gradual Discontinuation

If your child’s doctor decides it’s best to stop Zyrtec, they may recommend a gradual decrease in dosage. This is because sudden discontinuation might lead to withdrawal symptoms such as intense itching.

Tips for Parents

Here are some tips for parents dealing with their child’s behavioral changes due to Zyrtec:

  1. Stay Calm and Patient: Changes in your child’s behavior can be stressful for both of you. It’s important to stay calm and patient, offering your child comfort and reassurance.
  2. Communication is Key: Talk to your child about what they’re feeling. Even if they can’t fully articulate their feelings, this can help them feel understood and supported.
  3. Stay Informed: Learn about the potential side effects of any medications your child is taking. This can help you spot any issues early on.
  4. Seek Support: Don’t hesitate to reach out to other parents or support groups. Sharing your experiences and hearing from others in similar situations can be beneficial.
  5. Prioritize Healthy Habits: A balanced diet, regular physical activity, and adequate sleep can boost your child’s overall health and may help manage their symptoms.

In conclusion, while Zyrtec is a commonly used medication for allergy relief in children, it’s important to be vigilant about potential side effects, including behavioral changes. With careful monitoring and regular communication with your child’s healthcare provider, these issues can be effectively managed.

Alternatives to Zyrtec

If you notice unusual behavior in your child after administering Zyrtec, it’s important to consult your child’s doctor immediately. You may need to consider other allergy medicines or alternative treatment methods for your child’s allergies.

Other Allergy Medicines for Children

While Zyrtec is a widely used allergy medicine for children, it’s not the only option available. There are various other allergy medications that can be used as alternatives. Remember, it’s crucial to discuss with your child’s doctor before making any changes to their medication.

Claritin (Loratadine)

Claritin is another antihistamine designed to combat allergy symptoms such as a runny nose, watery eyes, and itching. It’s less likely to cause drowsiness, which makes it a suitable choice for daytime use. However, like all medications, it can still cause side effects, including headache, stomach pain, and dry mouth.

Allegra (Fexofenadine)

Allegra is also an antihistamine that provides relief from allergy symptoms. It’s less sedating than some other antihistamines, but it still may cause side effects such as vomiting, fever, or cough.

Benadryl (Diphenhydramine)

Benadryl is an older antihistamine and is often used for acute allergy symptoms or allergic reactions. However, it can cause significant drowsiness and is usually not the first choice for regular use in managing seasonal allergies.

Singulair (Montelukast)

Singulair is a leukotriene receptor antagonist, a different class of medication that’s often used for both allergies and asthma. It works by blocking leukotrienes, substances in the body that cause allergy symptoms. However, it’s worth noting that Singulair has been linked to mood changes and suicidal thoughts in some cases, so it’s essential to monitor your child closely if they’re taking this medication.

Natural Remedies for Allergies

In addition to medication, there are also natural remedies that can help manage your child’s allergy symptoms. These should not replace medical treatment but can be used alongside to provide additional relief.

Saline Nasal Rinse

A saline nasal rinse can help clear the nasal passages of allergens and reduce symptoms like a runny nose and congestion. This can be particularly helpful during the allergy season.


For children over one year, local honey can help build immunity to local allergens. However, honey should never be given to children under one due to the risk of botulism.

Maintaining a Clean Environment

Regular cleaning of your home, especially your child’s bedroom, can help reduce exposure to allergens. This includes washing bedding frequently, using air purifiers, and keeping windows closed during high pollen counts.


Quercetin is a natural antihistamine that can be found in foods like onions, apples, and berries. While it’s not a replacement for allergy medication, incorporating foods high in quercetin into your child’s diet may help manage their allergy symptoms.

As always, it’s important to discuss these remedies with your child’s healthcare provider before implementing them into your child’s allergy management routine.

Navigating the Allergy Season as Parents

As parents, seeing your child experience discomfort due to allergies is hard. And it’s even harder when the medicine supposed to help them leads to other issues. It’s crucial to keep a close eye on your child’s behavior and discuss any concerns with their healthcare provider.

When to Consult Your Child’s Doctor

If you notice any behavioral changes in your child after starting a new medication, it’s crucial to consult their doctor. It might be that your child is more sensitive to certain medications, or there could be other underlying factors at play.


While Zyrtec has proven to be an effective solution for many children’s seasonal allergies, it’s important to remember that every child’s reaction to medication can be different. If you notice behavioral changes in your child after taking Zyrtec, don’t hesitate to reach out to your healthcare provider. Always remember, when it comes to your child’s health, you’re their best advocate.



  1. Does Zyrtec have any side effects?Yes, like all medications, Zyrtec can have side effects. The most common ones include drowsiness, dry mouth, and occasionally, nausea.
  2. Can Zyrtec affect a child’s behavior?Yes, some reports suggest that Zyrtec can affect a child’s behavior. While it is not a commonly listed side effect, some parents have noted changes in their children’s behavior, including unusual mood swings, irritability, and hyperactivity, after starting Zyrtec. However, as each child is unique, not all children taking Zyrtec will experience these behavioral changes.
  3. What should I do if my child’s behavior changes after taking Zyrtec?If you notice any unusual behavior in your child after taking Zyrtec, it’s essential to consult your child’s doctor immediately.
  4. Are there alternatives to Zyrtec for children’s allergies?Yes, there are other allergy medications available, such as Claritin, Allegra, and Benadryl. However, always consult with your child’s healthcare provider before switching medications.
  5. Can natural remedies help with my child’s allergy symptoms?Certain natural remedies might offer relief, such as saline nasal rinses and honey (for kids over one year). However, they should not replace consultation with a healthcare provider.
  6. Can Zyrtec make a child hyper?While hyperactivity is not listed as a common side effect of Zyrtec, some parents have reported their children showing signs of hyperactivity after taking the medication. It’s important to note that individual responses to medications can vary, and what one child experiences may not be the same for another.
  7. Is hyperactivity a side effect of Zyrtec?Hyperactivity is not listed as a common side effect in the official documentation for Zyrtec. However, anecdotal reports from parents suggest that some children may experience hyperactivity after taking the medication. If you notice signs of hyperactivity in your child after starting Zyrtec, it’s important to discuss this with your child’s healthcare provider.
  8. Can antihistamines cause behavior problems?Some parents have reported behavioral changes in their children after taking certain antihistamines, including Zyrtec. These can include changes in mood, increased irritability, and hyperactivity.However, more research is needed to understand the potential link between antihistamines and behavior problems in children fully.


This post is written and edited by Sandy who is a clinical pharmacist with over 20 years of experience specializing in pre-natal and post-natal care.