About all

Can i take two zyrtec: Can You Take Two Zyrtec at Once?

Can You Take Two Zyrtec at Once?

Getty Images/AsiaVision

Allergies can be a moving target. Just when you think you’ve got your symptoms under control, the pollen count soars and you’re right back where you started. The popular allergy medicine Zyrtec (cetirizine) promises allergy relief with a single-tablet dose. But what if you take two doses—either accidentally or because you desperately need relief? Relax, say the experts. It’s not a great idea, but an isolated incident of taking two Zyrtec is unlikely to have major health effects.

In fact, some doctors double the dose of Zyrtec for their patients with severe hives if a single pill isn’t working. In general, though, “for anyone with typical allergy symptoms, there’s not a ton of evidence to suggest that that’s a good move without medical supervision,” says Marilyn Hill, Pharm.D., an ambulatory pharmacy manager at Dartmouth-Hitchcock Medical Center in Lebanon, NH. Popping two Zyrtec pills probably won’t hurt you, but there are better options, says Hill. If your allergies aren’t well controlled on a single 10-milligram pill, talk to your allergist or primary care doctor about other ways to reign in your symptoms.

How Safe Is Zyrtec at High Doses?

Still worried about your double dose? You should know that scientists have bumped up the dose of antihistamines like Zyrtec significantly without any major issues. In one study published in the journal Clinical and Translational Allergy, 138 people with chronic hives who didn’t improve on the normal one-pill dose were given four times the usual dose of antihistamines similar to Zyrtec. Ninety-seven people still didn’t respond to the fourfold dose. Of them, 59 people then were given a combination of two different antihistamines for a total of eight times the typical dose.

What happened? Almost half of people who got more than a fourfold dose had fewer or no hives (which means more than half didn’t see an improvement). About one in five people had side effects from high-dose antihistamines—mainly sleepiness. But even taking up to eight times the standard dose didn’t cause any serious side effects.

Some antihistamines affect what’s known as your QT interval—a measurement of the heart’s rhythm. Having a prolonged QT interval can lead to a dangerous irregular heart rhythm. Zyrtec has been tested at up to five times the normal dose without lengthening QT intervals, according to a study in the Journal of Cardiovascular Electrophysiology.

Zyrtec Side Effects

All of which is to say: Zyrtec is a relatively safe drug, according to J. Russell May, Pharm.D., a clinical professor of pharmacology at the University of Georgia College of Pharmacy in Augusta, GA. “Drowsiness would be the main risk,” he says. “If somebody has to go on a drive or be alert for whatever reason, I would not double up on Zyrtec, for sure.”

Other common side effects with Zyrtec, noted in an overview of the drug from the National Library of Medicine, include:

  • Dizziness

  • Dry mouth

  • Sore throat

Children who take Zyrtec have these same side effects. Kids are also more likely to have headaches, even at normal doses, says Dr. May. Some kids also have belly pain.

Dangers of Antihistamine Overdose

Overdosing on Zyrtec rarely results in emergency room-type consequences, says Hill. In studies, lab animals had to be given 460 times the recommended dose to have life-threatening effects, according to the National Library of Medicine.

But because your liver processes any medications you take, liver damage could be a problem, especially in older adults whose bodies break down medications more slowly and in people who already have liver disease. There have been reports of people developing jaundice and other symptoms of a liver problem, or having abnormal liver function tests while taking Zyrtec for several days, according to a review of cetirizine-caused liver damage in the journal Gastroenterology Report. Liver function returned to normal after they stopped taking this medicine.

Antihistamine Overdose Symptoms

The first clue that you’ve taken too much of any antihistamine is that you’ll feel more tired than usual. “If somebody’s feeling sleepy or has dry mouth, definitely talk to your provider,” says Hill. “Those are the kinds of side effects that you might experience if you do double up.”

Again, while side effects are generally mild and overdosing on Zyrtec is nearly impossible at toxic levels, drowsiness and dry mouth are signs that you shouldn’t be taking more than one Zyrtec pill, Hill adds.

What to Do If You Accidentally Take Two Zyrtec Pills

It’s natural to worry if you realize you’ve accidently doubled your dose, but in most cases, you won’t need to do anything if you mistakenly take two pills. Even children usually don’t need treatment after a double dose. Just manage any symptoms you or your child has.

Do be more cautious after you’ve taken a higher dose, though, and definitely stay off the road. “Know that you’re probably going to be drowsy. I wouldn’t be driving a car or doing other things that require you to be mentally alert,” Dr. May says.

When to Seek Emergency Help

The good news: You shouldn’t need emergency medical help for taking double the dose of Zyrtec, unless it’s your first time taking Zyrtec and you have a severe allergic reaction. It might sound odd that an allergy medicine can cause an allergic reaction, but it can happen (not due to a double dose, simply because your body is allergic to any amount of the medicine). Look for symptoms like these:

  • Nausea or vomiting

  • Swelling of your mouth, lips, or tongue

  • Trouble swallowing

These symptoms require emergency medical assistance, says Dr. May. Call 911 or go to an emergency room right away. If you’re in doubt about what to do after you or your child takes too much Zyrtec, call your local pharmacy or the Poison Control Center (800-222-1222) for advice, Hill advises.

Bottom line: Although Zyrtec probably won’t hurt you if you take too much, following the dosing instructions on the bottle is still the best approach to taking this—and any other—antihistamine. Says Hill, “More is not better. Over-the-counter drugs are still drugs.”

Notes: This article was originally published July 12, 2008 and most recently updated May 30, 2023.

Safety of High-Dose Antihistamines: Clinical and Translational Allergy. (2017.) “Effectiveness and Safety of Antihistamines Up to Fourfold or Higher in Treatment of Chronic Spontaneous Urticaria.” https://ctajournal.biomedcentral.com/articles/10.1186/s13601-017-0141-3#Sec7

Effects of Zyrtec on QT Interval: Journal of Cardiovascular Electrophysiology. (2007.) “The Effect of Antihistamine Cetirizine on Ventricular Repolarization in Congenital Long QT Syndrome.” https://pubmed.ncbi.nlm.nih.gov/17506855/

Zyrtec Side Effects: StatPearls. (2023.) “Cetirizine.” https://www.ncbi.nlm.nih.gov/books/NBK549776/

Liver Damage from Zyrtec: Gastroenterology Report. (2018.) “Cetirizine-Induced Hepatotoxicity: Case Series and Review of the Literature.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6101603/

Our Review Process

Symptoms and what to do

Taking too much antihistamine can lead to adverse side effects and a potential antihistamine overdose.

Antihistamines are a class of medication that treat allergy symptoms, such as sneezing, runny nose, and itching. As with any medication, taking too much can be harmful. Some antihistamines also work as sleep aids, cold and flu medicine, and motion sickness treatment.

People should follow the dosage guidelines on the packaging or their doctor’s advice to avoid an overdose. They should also keep antihistamines, and all medications, out of reach of children.

Always call a doctor or a poison control center if an antihistamine overdose occurs.

Share on PinterestA person who overdoses on antihistamines may experience fever, dilated pupils, and a fast heart rate.

People can overdose on any type of antihistamine. Antihistamines are a drug, and there is a safe limit to how much a person can take at one time.

This limit depends on several factors, including:

  • the age and size of the person
  • the type of antihistamine they took and how much
  • any health conditions they have
  • other medication the person takes

If a healthy adult takes only a slightly higher dose of antihistamine, such as accidentally taking two pills instead of one, their symptoms may not be serious, or they may not have any symptoms.

However, a larger overdose, especially in children or older adults, may cause serious symptoms. Toxic doses of antihistamines may happen when a person takes 3 to 5 times the normal amount.

No matter how much a person overdoses, they should seek medical help or call a poison control center.

A position statement from the Canadian Society of Allergy and Clinical Immunology (CSACI) states that first generation antihistamines can have “intolerable and potentially life threatening adverse effects.”

Research shows that first generation antihistamines can have effects on the central nervous system in large doses.

Examples of first generation antihistamines include:

  • diphenhydramine (Benadryl)
  • chlorpheniramine
  • brompheniramine

These antihistamines may cause jitteriness or drowsiness.

Second generation antihistamines do not usually have these effects. Second-generation antihistamines are commonly used medications, including:

  • loratadine (Claritin)
  • cetirizine (Zyrtec),
  • fexofenadine (Allegra)

Signs and symptoms of antihistamine overdose in children may include:

  • being very excited or jittery
  • a fast heart rate
  • irritability
  • hallucinations
  • seizures

After these symptoms appear, a child may experience:

  • drowsiness
  • slowed breathing
  • coma

Symptoms of antihistamine overdose in adults may include:

  • fever
  • flushing
  • dilated pupils
  • fast heart rate (tachycardia)
  • low blood pressure (hypotension)
  • coma
  • an inability to empty the bladder completely (urinary retention)

Second generation antihistamines tend to be less serious with an overdose. However, any overdose can be dangerous, and people should seek help from a medical professional or poison control immediately.

If a person suspects an antihistamine overdose, they should call the American Association of Poison Control Centers (AAPCC) at 1-800-222-1222. The AAPCC helpline is open 24 hours and is toll-free.

If a person has severe symptoms, such as trouble breathing, fast or slow heart rate, seizures, or loss of consciousness, call 911 or go to the nearest emergency room.

Some antihistamines are safe for children to take. However, the Food and Drug Administration (FDA) caution that just because a product says it is for children does not mean a child of any age can take it.

Research on antihistamines says that children and older adults are more at risk of an antihistamine overdose than adults.

One study found that children have experienced heart problems, seizures, and even death from an antihistamine overdose. The most common reactions are mild, however, and include:

  • rashes
  • sleepiness
  • headache

Second generation antihistamines are less likely to cause toxicity in children than first generation ones, according to a study of more than 9,000 children.

However, another study foundthat second generation antihistamines can cause dangerous symptoms when children overdose on them.

Diagnosing an antihistamine overdose usually starts with a discussion about all medications the person is taking and not just the antihistamines. This is because some other medications, such as cold, flu, and sleep medications, contain antihistamines.

If a person takes one of these other medications and also takes an allergy medication, they may accidentally overdose.

Other medications, such as certain antidepressants and motion sickness drugs, can also cause an overdose if a person mixes them with antihistamines.

If someone is not sure about the amount of antihistamine they took, a doctor may need to conduct a physical exam. They may look for signs such as drowsiness, irritability, blurred vision, or seizures. They may also check the heart rate, breathing rate, and blood pressure.

In some cases, a person may need blood tests or further observation in a hospital.

In mild cases, an individual may be able to use self-care at home. However, they should always call the AAPCC or a doctor to be sure this is safe.

If the person is experiencing serious symptoms, they may need hospitalization, including heart monitoring, intravenous (IV) fluids, and medication.

In some cases, doctors may give a person activated charcoal, which helps prevent the absorption of some medications and chemicals in the gut. They may also use ipecac syrup, which causes the person to vomit. This can cause any excess medication to leave the body in the vomitus.

Antihistamines may be first generation (sedating) or second generation (nonsedating). These two types may lead to different reactions if a person takes too much.

First generation antihistamines are more likely to cross the blood-brain barrier. This means they can make people dizzy or drowsy, even in normal doses.

Second generation antihistamines are newer drugs and are less likely to have these effects. Nonetheless, people can overdose on both types.

First generation antihistamines available over-the-counter include:

  • diphenhydramine (Benadryl)
  • chlorpheniramine (Chlor-Trimeton)
  • brompheniramine (Dimetapp)
  • clemastine (Tavist)
  • doxylamine (Unisom)
  • hydroxyzine (Vistaril)
  • promethazine (Promethegan)
  • triprolidine (Actidil)

These medications can act as sedatives, so they can make a person feel tired or dizzy.

Some experts say first generation antihistamines are more likely to result in death from accidents or overdoses than their second generation counterparts.

Second and third generation antihistamines available over the counter include:

  • cetirizine (Zyrtec)
  • fexofenadine (Allegra)
  • loratadine (Claritin)

These newer antihistamines are less likely to cause drowsiness and dizziness. Research has found them less likely to cause dangerous effects if a person takes too much.

Antihistamines are typically safe when a person takes the correct amount. However, as with any medication, they can cause serious adverse effects if someone takes too much.

People must keep antihistamines and all medications out of reach of children. Some antihistamines are safe for children to take, but it is important to ask a doctor or pharmacist about the right dose.

Different antihistamines have different dosages. It is vital to read labels carefully to be sure a person is not taking too much.

If an overdose happens, seek immediate medical attention or call the AAPCC at 800-222-1222.

Rules for transporting drugs on an airplane


Reading 6 min.
Views 29680

Posted by
Author Elena Petrovskaya

Carrying medicines on an airplane is a whole science with many nuances. Where can a specific drug be transported – in hand luggage or baggage, in what form, quantity, with or without a prescription? How do the rules differ depending on the status of the flight – domestic or international? Analysts of the Unitiket.ru blog have collected all the information on this complex issue for you.


Rules for transporting medicines on an airplane

Most medicines can be carried on an airplane without special conditions

A tourist can take medicines from Russia in the amount he needs, but if there are more than 5 identical packages, they must be declared. Also in this case, you should pay a fee (considered as a commercial batch), and control should pass through the red corridor.
The main rule: all medicines must be in their original packaging and with a valid expiration date.
A standard tourist kit does not require any special permissions, including prescriptions. If each medicine is presented in an amount of less than 5 packages, there is no need to specifically warn about such a first-aid kit and you can safely walk along the green corridor.

When a prescription is needed

The prescription must be signed and stamped by the doctor UniTicket recommends:

  • Look for cheap flights on aggregators: UniTicket , Aviasales
  • Search for

  • hotels at Ostrovok , Yandex Travel . And apartments at Sutochno.ru .
  • Compare rental car prices better at EcomonyBookings or LocalRent
  • Go on an unforgettable author’s journey YouTravel

If drugs contain narcotic and psychotropic substances, a doctor’s prescription is required. It must contain the personal signature of a specialist and the seal of a medical institution.

The prescription must indicate the frequency and exact dosage of the drug. And if the flight is carried out abroad, do not forget to translate the document into English and certify it with a notary.

Particular attention should be paid to the composition of:

  • sleeping pills;
  • painkillers;
  • sedatives;
  • heart;
  • diuretics;
  • antitussives;
  • antibiotics.

Which drugs cannot be transported

The list of medicines prohibited for import varies from country to country. You can get acquainted with it in the customs regulations. However, medicines based on narcotic and psychotropic substances without a prescription are prohibited for import in almost all countries.

If you are going to take a first aid kit on the road, be sure to study the rules of the country of arrival.

Sometimes drugs that are actively used in Russia and sold without a prescription are included in the banned list. So, in many countries they will not let Corvalol and Valocordin (they have active narcotic substance phenobarbital), including to the Baltic countries, the USA and the UAE, and analgin (metamisole sodium) – to the European Union, USA, Australia, part of Asian countries.

Familiar to us analgin is prohibited for import in many countries

Please note: the ban does not apply to a specific drug, but to a substance. That is why it is important to study the composition. The banned substance can even be found in products such as weight loss tea.
In particular, prohibited substances in many countries include:

  • codeine;
  • chlorphenamine;
  • phenobarbital;
  • nimesulide;
  • metamizole sodium;
  • ephedrine;
  • diazepam;
  • melatonin.

Complete lists of substances prohibited for export and import into Russia are presented on the website of the Central Customs Administration http://ctu.customs.ru

In case of violation of the rules for transporting medicines, the consequences can be the most unexpected. In the best case, the passenger will be asked to throw away the medicines, in the worst case, they will be removed from the flight or even put in jail.

Prohibited medicines without a prescription will be sent to such a container

Medicines in carry-on baggage

It is easier and more convenient to transport a first aid kit in your luggage, taking only the necessary minimum of medicines into the cabin. However, if you have drugs in liquid form on the mandatory list, their transportation must comply with the general rules for transporting liquids in hand luggage.

  1. Containers up to 100 ml.
  2. The total amount of liquids together with medicines – no more than 1 liter.
  3. Fluids are packed in a zip-lock plastic bag.

If it is vital to carry a medicine with a capacity of more than 100 ml, confirm this with a doctor’s prescription.

Dry ice will help to create a necessary condition for some medicines – a low temperature. It can be taken in hand luggage in the amount of 2 kg.

This is what a first-aid kit should look like in cabin baggage

How to carry ampoules and syringes in cabin baggage

The content of ampoules is liquid, so they must comply with the general rules for carrying liquids in cabin baggage and be clearly labeled. Ampoules should be carried in baggage, except for the amount that may be required during the flight. Particular attention to insulin: it must be carried in hand luggage, because. in the luggage compartment, it can lose its properties under the influence of low temperatures.
Needles are classified as dangerous items, so syringes can only be transported in luggage. An exception is vital situations, confirmed by a doctor’s report. In this case, you can take syringes and ampoules with you in the amount necessary for the duration of the flight.

Ampoules and syringes can be taken in hand luggage only in exceptional cases

The passenger must notify security services about the presence of needles in hand luggage. Throw away used syringes in the cabin of the aircraft in a special container for sharps. The stewardess will provide it upon request.

What medicines to take on the plane

As a rule, medicines on the plane are a mini version of the traveler’s first aid kit.
Tourist’s classic first aid kit includes:

  • enterosorbents (for indigestion) – activated charcoal, neosmectin, enterosgel;
  • antihistamines (anti-allergic) – zyrtec, cetrin, suprastin;
  • anti-cold — arbidol, rimantadine;
  • antipyretics (they are also light painkillers) – paracetamol, nurofen;
  • antiseptics – brilliant green, hydrogen peroxide, iodine.

Every salon has a first aid kit, to use it, you need to contact the stewardess.

More ideas for your holidays! (Baggage):

Copyright © 2016-2023. All rights reserved. UniTicket.ru is part of HolidayPrice Inc., the European leader in online tourism and related services. Privacy policy.Terms of use.Site map. When using materials, an active link to the site UniTicket.ru is required.

How to overcome allergies: selection of medicines, first aid kit, first aid

“An attack can start suddenly. Here lived a man in the city and did not feel anything. And then I went out of town for a barbecue and fell down there, ”says Elena Antsiferova, an allergist-immunologist, candidate of medical sciences, head of the Evadoctor school for pregnant women.

What allergy medications should be in the first aid kit. Why suprastinex (from 274 rubles) is more suitable for one person, and zyrtec (from 183 rubles) for another, and how to determine what is best for you. What antihistamines can be mixed with alcohol.

A short course on dealing with allergies – from the site vseapteki.ru.

Allergy medicines are available

Allergy medicines are also called “antihistamines”. Histamine is a chemical in our cells. When the allergen enters the body, histamine is released and provokes painful reactions: sneezing, runny nose, swelling, itching.

All antihistamines are conditionally divided into three generations. Of the first, diazolin (from 82 rubles), tavegil (from 158 rubles), diphenhydramine are the most famous. From the second – claritin (from 218 rubles), zirtek (from 183 rubles), lomilan (from 116 rubles), lorahexal (from 54 rubles). Of the third – fexadine (from 295 rubles), erius (from 633 rubles).

“The higher the generation of the drug, the fewer side effects it gives,” says Elena Antsiferova. First-generation antihistamines have a pronounced sedative effect: they cannot be mixed with alcohol, taken at work, where concentration is needed. Second-generation antihistamines are given with caution to people with heart disease. These drugs can have a cardiotoxic effect, complicate the work of the heart. It is believed that the third generation of allergy drugs is the most “clean”: they are practically devoid of “side effects”.

What should be in an allergy first aid kit

New generation drugs are more versatile. Despite this, it is better to have two or three allergy medicines of different generations in the medicine cabinet. For example, the “old” diazolin (from 82 rubles) and the “new” claritin (from 218 rubles) and zirtek (from 183 rubles).

“In a situation where a person was bitten by a bee or a midge, and an allergy attack developed rapidly – with swelling, fever and shortness of breath, suprastin can help faster than new drugs,” says the expert of the site vseapteki.ru.

Why do you need allergy medicine if you are not allergic?

Many people don’t even know they have allergies. “Seasonal” allergic exacerbations begin in spring and summer – in connection with the flowering of trees and grasses. In the city, the concentration of allergens is less: a person feels very slight ailments and thinks that he has a cold.

But then he will go to nature and end up in the areas of flowering cereal grasses – couch grass, foxtail, timothy grass, bluegrass: they provoke most allergic reactions in central Russia in early summer. And an attack will happen – the Erius at hand will help to quickly stop it (from 633 rubles).

Elena Antsiferova

Allergist-immunologist, candidate of medical sciences, head of the school for pregnant women Evadoctor

If a person does not suffer from annual allergic reactions, you can have only one antihistamine in the first-aid kit – the best of the latest generations.

At risk are people who have relatives with allergies, who annually suffer from a “spring-summer” cold (it always starts and ends at about the same time), who have bronchial asthma, skin diseases.

Is it possible to drink one allergy medicine all the time

First-generation allergy medicines are used in short courses – 2-3 weeks on average. Then the body adapts to them: the antihistamine activity of the drug decreases. Preparations of the second and third generations can be drunk year-round, if there are no contraindications.

“With age, the body’s reactivity changes, the number of diseases increases. Therefore, the relevance of antihistamines needs to be confirmed by a doctor from time to time, ”says Elena Antsiferova.

What to do if you don’t have allergy medications at hand

  • If you have hay fever (allergy to plant pollen) – wash off the pollen: wash your eyes, face and hair. It is in the hair that pollen settles the most. Change clothes. Wear a bandana and sunglasses.
  • If you are allergic to food, drink water. If the attack intensifies, artificially induce vomiting.
  • If you are allergic to insect bites – apply cold to the bite (a bottle of water, a wet towel, a bag of earth).