Less common side effects include headaches, and nausea.Diarrhea and coughing have also been observed in children.

Zyrtec can increase the drowsiness triggered by other medications.

Interestingly, researchers have found that children tolerate cetirizine-related drowsiness better than adults.

A woman with allergies blowing her nose

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How Long Does Zyrtec Stay in Your Body?

With an elimination half-life of eight to nine hours, Zyrtec remains in your system for about two days.

Rare Side Effects

Rare side effects from Zyrtec can include:

Anaphylaxisis possible when taking Zyrtec.

When to Call 911

Rarely, Zyrtec can cause a potentially life-threatening, whole-body allergy known asanaphylaxis.

Zyrtec should not be taken with alcohol or marijuana.

Doing so can increase the risk of drowsiness and can make driving or handling heavy equipment hazardous.

Each dose is measured in milligrams (mg).

There are recommended dosages for specific age groups.

However, the recommended dose of Zyrtec for those in this age group is lower than for younger adults.

For children under 2:

Zyrtec is taken with or without food.

Measure the syrup using the dosing syringe provided andnota kitchen spoon.

Chewable tablets should be chewed and not swallowed whole.

Can Taking Zyrtec Daily Be Harmful?

However, these OTC drugs have similar mechanisms of action to Zyrtecand similar potential side effects.

So, they may not be an option if you cannot tolerate the side effects of Zyrtec.

Limited research has demonstrated that some essential oils can ease sinus inflammation.

It is available OTC for use in adults and children.

Side effects can include drowsiness, dry mouth, sore throat, dizziness, and stomach pain.

Serious side effects can include rapid or irregular heartbeat, mood changes such as anxiety, and problems urinating.

Zyrtec is an effective option for treating seasonal allergies and other allergic conditions.

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