Is it better to take Zyrtec at night or in the morning?

In this article:

• Is it better to take Zyrtec at night or in the morning?
• Considerations for timing
• Missed dose
• Personalizing your treatment
• The bottom line

In this article

• Is it better to take Zyrtec at night or in the morning?
• Considerations for timing
• Missed dose
• Personalizing your treatment
• The bottom line

Zyrtec (cetirizine) is an over-the-counter (OTC) antihistamine approved by the FDA to treat seasonal allergies, hay fever (allergic rhinitis), and allergic reactions. It’s in the same drug class as Allegra (fexofenadine), Claritin (loratadine), and Benadryl (diphenhydramine). These allergy medications block histamine receptors, leading to symptoms such as sneezing, itchy eyes, watery eyes, runny nose, stuffy nose, hives, and sore throat.

Unlike first-generation antihistamines—such as diphenhydramine—Zyrtec is much less likely to cause drowsiness. Does that mean patients “should” take it in the morning? Or what time of day is best?

The most common dosage for adults is 10 mg once daily, as needed. The time depends on various factors, primarily what you’re allergic to and when you encounter those allergens.

Is it better to take Zyrtec at night or in the morning?

There’s no set time of day that’s best for taking Zyrtec. According to a 2018 study in Allergy & Rhinology, cetirizine provides 24-hour allergy relief regardless of when you take it. It also kicks in within 30 to 60 minutes (so pretty quickly).

Ultimately, the answer comes down to what works best for each individual. “This will be on patient preference,” says Dr. Kanwar Kelley, MD, JD, a board-certified otolaryngologist (ENT) and co-founder and CEO of Side Health. “The medication will affect everyone differently, so it is better to cater to when you are more likely going to experience symptoms.”

One question that might arise is whether taking Zyrtec at night can improve sleep quality by reducing allergy symptoms. Dr. Raj Dasgupta, MD, chief medical adviser for Fortune Recommends and a quadruple board-certified physician, speaks to how a night dose can indirectly improve sleep quality (if allergies keep you up) “by reducing symptoms like nasal congestion, sneezing, and itching.”

Dr. Kelley adds that specific triggers, such as pet dander and dust, may also call for taking Zyrtec at night.

However, taking Zyrtec at night isn’t necessarily the more popular choice. “Most people take Zyrtec in the morning, which can address allergy symptoms without causing drowsiness,” Dr. Dasgupta says. “Some people may still experience mild drowsiness, so it’s important to see how your body responds.”

If Zyrtec does make you feel drowsy, Dr. Kelley suggests looking for alternative treatments, such as avoiding allergens and nasal saline irrigations. 

Considerations for timing your Zyrtec dose

If some people prefer taking Zyrtec at night and others prefer morning, is there a “best” time? “The best time to take Zyrtec depends on your daily routine,” says Dr. Dasgupta. While that factor is flexible, he urges taking it around the same time every day.

Dr. Kelley encourages taking it in anticipation of when you’ll experience the most symptoms. If allergies bother you more during the day, a dose in the morning may be the answer; if they keep you awake at night, consider taking then. For example, if you’re allergic to grass, you may want to take it when you wake up. But if dust mites are your biggest problem, taking it before bed might be key.

Again, Zyrtec typically doesn’t make people drowsy, so that isn’t a deciding factor. It doesn’t work like melatonin or a sleeping pill, and it won’t make you tired in the morning. If you feel tired in the morning, it’s probably not because of the Zyrtec. “There may be other factors that lead to grogginess in the morning,” Dr. Kelley says. “Looking into other causes could help with the morning symptoms.” A couple of examples include chronic fatigue syndrome and disrupted sleep.

What to do if you miss a dose of Zyrtec? 

If you miss a dose of Zyrtec, you can take it later—if it’s on the same day. However, you should only take one day’s worth; don’t take two doses in one day.

Personalizing your allergy treatment plan

First and foremost, knowing what you’re allergic to is crucial. If you’re not sure—or even if you know some triggers but possibly not others—consider allergy testing with a medical professional.

When creating your individualized allergy treatment plan with a healthcare provider, keep those allergens in mind. They inform you when you take the allergy medicine and how to alleviate or reduce your symptoms. 

It’s important to note here that the common side effects of Zyrtec might look like allergy symptoms: headache, sore throat, dry mouth, cough, and other allergic reactions. Side effects that are less common and more severe include low blood pressure, airway closure, dizziness, a fast heartbeat, and more. That’s also where other treatment options come in.

Besides Zyrtec, other allergy treatments and OTC medications include decongestants, immunotherapy, air purifiers, inhaling steam, supplements, and more. Nasal sprays, such as Flonase, are another effective option for treating allergies.

“You can also reduce allergens around your home by keeping windows closed, using air purifiers, or minimizing outdoor exposure during peak allergy season,” Dr. Dasgupta says. “Tailoring your approach based on your schedule and symptoms will help you find the most effective treatment.”

Again, don’t forget the importance of not doing this alone; consult with a healthcare provider when determining an appropriate allergy plan. The professional can assess what would be most helpful for each person specifically.

Zyrtec (and other allergy meds) can be purchased at a lower cost by using a SingleCare prescription discount card.

The bottom line

To ensure optimal effectiveness and minimal side effects, consider when you encounter allergens and take Zyrtec right before that period. Also, remember to engage in ongoing dialogue with a healthcare provider, such as an allergist. They have extra insight and can help you adjust your treatment plan as needed.