what is levocetirizine

What is Levocetirizine? This New OTC Antihistamine Is No Different Than the Others

In Antihistamine Addiction, Environmental Allergies by Anthony9 Comments

Levocetirizine, also known by Xyzal, is a prescription antihistamine used to treat the symptoms of allergic rhinitis and hives that is going to become available over-the-counter in drug stores. Its function is to prevent the actions of histamine in the body, which produces itching, sneezing, congestion, runny nose and closing of the airways. Since it is new to the market, you may be wondering if it is more effective or safer than other antihistamine drugs. What is levocetirizine and should we switch to it for those harsh days?

This website tries to treat the root causes of allergies, while antihistamines only mask the symptoms of the true problem. While it is understandable that you would want to avoid using drugs, it would be unpractical to take advantage of them when you need them most in your life. Many people have demanding lives and cannot be sneezing and feeling groggy all day.

Therefore, it is wise to keep one of these antihistamine brands available for those emergency days.

Levocetirizine goes for almost $1 per dose in stores, which I think is ridiculous. This is where I get it online for 70% cheaper.

What is Levocetirizine?

Levocetirizine comes in the form of a pill and in a diluted solution, which is taken orally. It is bought under the brand name Xyzal and also as a generic drug. This drug can be used to treat the symptoms of seasonal and year-round allergy symptoms as well as treating the itching caused by hives. (1)

In severe allergy patients, levocetirizine will be used in a combination therapy with other drugs like steroids.

If you are reading this, you are probably the type of person like myself to prefer a more natural approach. However, some days are very detrimental to my allergy symptoms and I need a strong antihistamine to be productive throughout my day.

I usually keep an Allegra allergy medication on hand and I was considering switching to this new over-the-counter drug because antihistamines added to the free market usually get progressively better.

This time, however, it is not the case: levocetirizine is not a better antihistamine.

This is considered a “third-generation” non-sedative antihistamine derived from the second-generation cetirizine. As a chemical, levoceterizine is the active enantiomer of cetirizine. An enantiomer is a compound with the exact same makeup of atoms, but in a different mirrored arrangement.

So, levocetirizine is exactly the same as cetirizine chemically, but slightly different just in the same way that your left hand is different from your right hand.

If you take this drug, it will prevent the release of inflammatory allergy chemicals that are produced by your body and will increase blood supply to the allergic area. It does not prevent the release of histamine from mast cells. (2)

what is levocetirizine

Mast cells of the human immune system.

Side Effects of Levocetirizine

Just like other prescription and over-the-counter drugs, levocetirizine will have the risk of developing mild or severe side effects.

If you experience these effects, be sure to contact emergency medical attention because they can be fatal:

  • Hives
  • Difficulty breathing
  • Swelling of the face, lips, tongue, or throat

These may be symptoms of an allergy to the chemical.

Non-fatal but still severe side effects can include:

  • Painful urination
  • Swelling of the urethra
  • Pain in the ear or problems hearing
  • Faintness or light-headedness
  • Fever
  • Worsening allergy symptoms
  • Nosebleed
  • Depression, agitation, aggressiveness, or hallucinations
  • Stomach pain or loss of appetite
  • Yellowing of the skin or eyes(Jaundice)
  • Numbing of the lips or mouth

If you experience these symptoms, stop taking levocetirizine and call your doctor.

Common and mild side effects of levocetirizine include:

  • Tiredness or weakness
  • Drowsiness
  • Fever
  • Congestion
  • Pain in the sinuses
  • Sore throat or cough
  • Vomiting
  • Diarrhea or constipation
  • Dry mouth
  • Bloating
  • Sleepiness
  • Headache
  • Blurred Vision
  • Heart palpitations
  • Fatigue

Everyone’s body is unique and you may experience different symptoms.

How Do You Take Xyzal?

You should always take prescription drugs as recommended by your doctor and follow the directions on the prescription label.

If your child was prescribed this medication, please take note that a child’s body absorbs at least twice as much of the drug as an adult.

Do not give your child the same dose as you would yourself, or even half.

Taking too much of this medication will cause dizziness and fatigue while not making it any more effective for your allergy symptoms.

Levocetirizine is usually directed to be taken in the evening before bed so that it may be active when you wake up in the morning.

If you have the liquid form, make sure that you use the dosing syringe or medicine cup to make sure that you are getting the correct amount. You can ask a pharmacist for one for free.

Keep this medication at room temperature, away from moisture, heat, and sunlight.


what is levoceterizine

Levocetirizine is cetirizine’s R-Enantiomer.


Important Precautions When Considering Levocetirizine

If you have kidney disease or are on dialysis, you should not take this medication and you should make your doctor aware of these conditions that you have.

It may also be important to notify your doctor of liver or gallbladder problems because this medication may complicate these health problems further.

If you are allergic to levocetirizine or cetirizine, also known as Zyrtec, you should not take this drug.

If you have conditions that give you problems with urination, like enlarged prostate or spinal cord lesion, you should reconsider this medication.

Pregnant and nursing mothers should not take levocetirizine because it can be transmitted to your baby through the bloodstream or breast milk. (3)

Drug Interactions With Xyzal

Alcohol will increase the nervous system side effects that can be experienced with levocetirizine. It can create a severe problem for dizziness, drowsiness and short-term memory loss. This drug combination will also impair thinking and judgment.

Definitely avoid alcohol when on this medication, especially when you are operating hazardous machinery.

Other allergy medications, sedatives, narcotics, pain relievers, sleep medication and antidepressants will give you adverse effects. They can worsen depression, anxiety and insomnia. (4)

It is most important to avoid taking ritonavir(Norvir, Kaletra) and theophylline(Aquaphillin, Asmalix, Theolair, Theosol) supplements when considering levocetirizine.

This list will never be complete and other drugs and supplements can interact with levocetirizine, as well as food. This includes vitamins and herbal products.

What is Levocetirizine (Xyzal) Compared to Cetirizine(Zyrtec)?

Xyzal is considered a third-generation antihistamine that comes after the second-generation Zyrtec. You have to take half the amount of levocetirizine to get the same effect as Zyrtec. They are both essentially the same compound that work to block histamine receptors.

One of the claimed differences is that Xyzal will bind more effectively to the receptor sites and it has been said to be safe for infants at six months of age. Zyrtec is not intended for small children. However, Xyzal is not available in a chewable like Zyrtec is. (5)

Xyzal and Zyrtec are both considered non-sedative, but Xyzal can cause drowsiness. (6)

What is Levocetirizine (Xyzal) Compared to Fexofenadine(Allegra)

Two studies involving adults with seasonal allergic rhinitis tried to compare levocetirizine and fexofenadine in terms of symptom relief and improving quality of life. The study polled the participants and they had concluded that symptom relief was equal between the two drugs.

However, the participants voted that their quality of life had improved much more with Allegra. (7)

In terms of safety, levocetirizine is deemed much safer for use on children suffering from allergies.

It seems that Allegra users report much fewer side effects than those taking levocetirizine. (8)

Should We Consider Switching to Levocetirizine?

Research has proven that this medication can reduce asthma attacks by 70%. It is considered a generation above Zyrtec that is non-sedating and does not enter the brain in large amounts.

Levocetirizine had been approved for over-the-counter sale on January 31, 2017 by the Food and Drug Administration. At that point, it had already been available in stores in most European countries.

In my opinion, regular Zyrtec or Allegra would be a more effective use of your money. From the research that has been gathered so far on this new drug, it seems that it is not more effective than Zyrtec or Allegra when it comes to relieving allergy symptoms. This is because it had never been formally proven better than a second-generation antihistamine like cetirizine.

I have written before that everybody reacts differently to antihistamines and should experiment with different ones to see which works best for you. Although I recommend avoiding these drugs and only using them when needed, I find that Allegra brand antihistamine works best for me.

For those emergency days when life is demanding and you don’t want to deal with your severe allergy symptoms, try to find the brand of antihistamine that works best for you if natural methods are not effective enough.

I am always here for you, so feel free to talk to me in the comments.


What is Levocetirizine? This New OTC Antihistamine Is No Different Than the Others was last modified: November 8th, 2018 by Anthony


  1. For the last few years it seems people complain that zyrtec, Claritin and Allegra do not work for them as well as they used to for those few bad weeks every year. And let’s not even go into the fact, that over the last few years, allergies have become much more widespread (climate change). I usually advise patients to cycle between the 3 different types each year because it seems like your body can develop a sort of tolerance. Adding the “D” into the medications is just a bad deal over all. It’s Sudafed. Which many people try to avoid and if they realised that’s what the “D” meant and what people use to make illegal methamphetamine, they would probably be upset it isn’t more transparent. And I definitely tell patients not to hooked on those OR Flonase for allergy symptoms. Now, Zyzal. I keep hearing patients bring this medication up and I am trying it myself this week to see how it works. But it seems like many people I’ve met swear by it. It could be that the different, mirror-shaped structure is just able to cause a different but stronger reaction within their bodies to relieve symptoms. Which is completely possible. Theres just so much we DON’T know. While I do think it’s true pharmaceutical companies create drug derivatives that are essentially the same product to make money, I also know that even a mirror molecular structure can create a completely different compound. Xyzal is a chiral drug which is not super imposable on zrytec. It has different pharmokinetic and pharmodynamic effects. For example, how thalomide ended up with drastically different effects from its isomers or even
    2,3,7,8-tetrachlorooxanthrene (form of dioxin) became a biological weapon. Anyway, if the others aren’t cutting it for you, it’s worth a try. And the side effect list isn’t any worse than the others. It’s actually considered safer.

  2. Was looking for info on the difference between xyzal and zyrtec and ended up here. I was on xyzal when it was prescription only, it actually worked and helped immensely with my hives. Once it went OTC it was definitely not the same and is basically placebo trash. zyrtec d is the only thing that works for me whatever is in that. anyone with knowledge would love to know whats going on with these allergy meds!

    1. Author

      You think OTC Xyzal is worse than the prescription version? I have never heard of that before, but maybe it is just a lower dose of levocetirizine?

  3. Hey Anthony, well, its a year later but i’ll comment anyway. I just got home from the dr. who prescribed this for me…..its new here. Im 67 and have COPD. For the last 3 mths Ive had this heavy feeling in the bottom of my lungs and terrible gasping for breath after hardly any exertion. i thought i had congestive heart failure. Ive seen 6 drs. over this including my pulmonary dr. This had really upset me me and im gasping for breath and theyre saying my lungs are clear. anyway, !! , im wondering why you seem so against antihistamines period. I always look up whatever i am prescribed and I’ve quit falling in the floor after reading the side effects. lol lol . so this doesnt really seem to bad for me; im hoping it will make me drowsy. I need sleep terribly. I just took it and hr ago. Well maybe you check in and you’ll read this. If i have any adverse ….. really adverse reactions, ill come back and let you know. If not, thank you for your input so millions of us can find it. Take care. tcc

    1. Author

      Hey Terrie,
      I think you might be stuck on a perspective that some false information is leading you through. First of all, I am definitely NOT against antihistamines at all. I think they are a wonderful innovation in medicine, just like fire is. They are tools that can do great things for us and possibly save lives. The point I am trying to make is that we are addicted to them for no reason, which creates a long-term problem. Also, drugs that make you drowsy don’t give you restful sleep. What you really need is rejuvenation from deeper sleep by activating the lower sleep waves during rest. Drugs that cause drowsiness and make you high make you unable to reach these important sleep stages. You should start there and do some research about that to begin your journey towards optimal health. Let me know what you think!

  4. Key things about this new version over their predecessor Zyrtec 1) it works as long as the old version, but you’re taking less to achieve the benefit of taking an antihistamine. 2) It doesn’t reach the brain as much, which can cause cognitive problems- safer. 3) less drowsy than the older, or maybe not at all. Price is higher, but that is what a mfg does with a newer version, which also differentiates the newer one from the older one.

    Antihistames are VERY well studied over all. They work differently for everyone, so try different ones, starting at a child’s version or low dose, depending upon how they are offered. A”D” version for some of these include a decongestant, which can be dangerous for some people, so using a plain one is safest.

    1. Author

      Awesome input about over-the-counter antihistamines. Great points, thanks a lot.

  5. Holy cow! That is a huge list of side effects. Is that normal for an OTC antihistamine? I mean when you start to talk about painful urination, swelling of the urethra, jaundice, hives, swelling (anywhere), those are things that seriously effect your life.

    I suffer from allergies off and on throughout the year but can normally knock it down with a few days of Allegra or Zyrtec, are their side effect lists like this? If they do have these kinds of side effects it is scary!

    I know you say that everyone reacts differently and so should try new allergy meds to test and see if they work for them but from everything I read it sounds like this is just a slightly different form of what’s already out there and probably just a way for pharmacies to get another product on the shelf, is that your take as well or do you really think people should invest time and money in trying this out?

    1. Author

      Hey there,

      For an over-the-counter antihistamine, these severe reactions are relatively normal because your body can be allergic to them. So we should always try to limit our consumption of antihistamines to prevent a dependence.

      That is actually exactly what I am saying. I think that the pharmacies are simply trying to market the same product for a profit. That’s probably why I’d trust a different antihistamine over this one. I don’t think that people should try this product, but if they have already tried it, I’d love to know if it worked for them.


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