Loratadine

 Risk Factor: BM
 Class: ANTIHISTAMINES

Contents of this page:

Fetal Risk Summary
Breast Feeding Summary
References
Questions and Answers

Fetal Risk Summary

Loratadine, a second-generation histamine H1-receptor antagonist, is used for the treatment of symptoms related to seasonal allergic rhinitis. Studies with rats and rabbits with oral doses up to 75 and 150 times, respectively, the maximum recommended human daily oral dose on a mg/m2 basis found no evidence of teratogenicity (1).

It is not known if loratadine crosses the human placenta. The molecular weight (about 383) is low enough, however, that passage to the fetus should be expected.

The FDA has received six reports of adverse outcomes following exposure during pregnancy, including two cases of cleft palate, and one case each of microtia and microphthalmia, deafness, tricuspid dysplasia, and diaphragmatic hernia (personal communication, F. Rosa, FDA, 1996). A relationship, if any, between loratadine and the outcomes cannot be determined from these data.

A 1998 non-interventional observational cohort study described the outcomes of pregnancies in women who had been prescribed one or more of 34 newly marketed drugs by general practitioners in England (2). Data were obtained by questionnaires sent to the prescribing physicians one month after the expected or possible date of delivery. In 831 (78%) of the pregnancies, a newly marketed drug was thought to have been taken during the 1st trimester with birth defectrs noted in 14 (2.5%) singleton births of the 557 newborns (10 sets of twins). In addition, two birth defects were observed in aborted fetuses. However, few of the aborted fetuses were examined. Loratadine was taken during the 1st trimester in 18 pregnancies. The outcomes of these pregnancies included 2 elective abortions and 16 normal, term infants (2).

Although no congenital malformations were observed in the above study, the data are too limited to assess the safety of loratadine. Moreover, the study lacked the sensitivity to identify minor anomalies because of the absence of standardized examinations. Late appearing major defects may also have been missed due to the timing of the questionnaires. If an oral antihistamine agent is required during pregnancy, first generation agents such as chlorpheniramine or tripelennamine should be considered. Loratadine and cetirizine are considered acceptable alternatives, except during the 1st trimester, if a first generation drug is not tolerated (3,4 and 5).

Breast Feeding Summary

Loratadine and its metabolite, descarboethoxyloratadine, are excreted into human milk (1,6). Six lactating women were given a single 40-mg dose (6). The peak milk concentration, 29.2 ng/mL, occurred within 2 hours of the dose, whereas the peak plasma level, 30.5 ng/mL, was measured 1 hour after the dose.

The mean milk:plasma area under the concentration curve (AUC) ratios for the parent compound and the active metabolite, measured during 48 hours, were 1.17 and 0.85, respectively (1,6). During 48 hours, the mean amounts of loratadine and metabolite recovered from the milk were 4.2 g (0.010% of the dose) and 6.0 g (equivalent to 7.5 g of loratadine; 0.019% of the dose), respectively. A 4-kg infant ingesting this milk would have received a dose equivalent to 0.46% of the mother's dose on a mg/kg basis (6). Based on this estimate, and the fact that the dose used in the study was 4 times the current recommended dose, there is probably little clinical risk to a nursing infant whose mother was taking 10 mg of loratadine per day.

References

1. Product information. Claritin. Schering Corporation, 2001.
2. Wilton LV, Pearce GL, Martin RM, Mackay FJ, Mann RD. The outcomes of pregnancy in women exposed to newly marketed drugs in general practice in England. Br J Obstet Gynaecol 1998;105:8829.
3. Mazzotta P, Loebstein R, Koren G. Treating allergic rhinitis in pregnancy. Safety considerations. Drug Saf 1999;20:36175.
4. Horak F, Stubner UP. Comparative tolerability of second generation antihistamines. Drug Saf 1999;20:385401.
5. Position statement of a joint committee of the American College of Obstetricians and Gynecologists and the American College of Allergy, Asthma and Immunology. The use of newer asthma and allergy medications during pregnancy. Ann Allergy Asthma Immunol 2000;84:47580.
6. Hilbert J, Radwanski E, Affrime MB, Perentesis G, Symchowicz S, Zampaglione N. Excretion of loratadine in human breast milk. J Clin Pharmacol 1988;28:2349.
   
   

Questions and Answers

loratadine?, Is loratadine (Claritin) ok to take when you are taking blood pressure medicine?

it should be fine, but ask your doctor or ask the pharmacist first to be safe.

What is the difference between loratadine and cetirizine dihydrochloride?, I've tried using both for my allergies. It says one is used to treat symptoms but loratadine is used to treat the whole allergy. Are there any other more effective choices that aren't too expensive?

Loratadine is Claritin and cetirizine is Zyrtec. They are both anti-allergy medication. They both treat the whole allergy. They are in a class called the anti-histamines. These medications are your best bet. Clarinex is another one, but it's no more effective than Claritin or Zyrtec. Just make sure you drink plenty of fluids when you take them, because they can dry you out a little. If the allergies keep up, go see your doctor.

Can Loratadine taken by children cause mood swings & suicidal thoughts?, My grandson-age 7 takes Loratadine, the generic of Claritin on a daily basis. His mother was told that it could possibly have serious mental health side effects. Have you heard of this and should he take it daily longterm anyway?

Did the physician give your daughter this info? Does the child have mood swings? There is another medicine in this category that has been linked to mental health problems. I cannot remember the name, but it is a commonly used medication. I take Claritin or it's generic, and have not experienced any problems. Tell your daughter to consult the pediatrician if she has concerns.

Can I take Diphenhydramine and Loratadine at the same time?, I use Claritin (Loratadine) for allergies everyday. Sometimes I find myself sleepless and have found Simply Sleep (Diphenhydramine) to be sometimes useful but sometimes find myself wide awake even longer. Now I'm wondering if this is smart since both are anithistamines. Is it counter-productive? Dangerous?

You probably should not take Diphenhydramine and Loratadine at the same time. They are both antihistamines... they work along the same medical pathway. There is the strong chance that you could overdose by taking both of them.

If you are having severe seasonal nasal/sinus allergies... I recommend Nasalcrom. Nasalcrom is a non-prescription medication originally produced to help fight children's asthma. It is a salt that binds to Mast Cells. Mast cells are the cells in your body that release histamine, thereby causing all your nasal problems. Nasalcrom binds to the mast cells and keep them from releasing the histamine in the first place.

Because Nasalcrom works on a different pathway, you can use it AND take an antihistamine without ill effect.

The only drawback? It takes 1 or 2 weeks for the salt to build up in your system enough to fight off the allergies. Basically, you need to start taking it before your allergy season hits, or as it just starting. You also have to take it pretty regularly at first (about every 4-6 hours). Still, it has few (if any side effects) and works great against nasal and sinus allergic rhinitis.

Will 50mg of loratadine be enough to kill someone?, Will 50mg of loratadine be enough to kill someone? If not, how much would?

No it wont because I have tried it before and all I got was a really bad headache that lasted about a few hours but after that I was totally fine.

Loratadine makes me drowsy, should I try cetirizine?, I've tried takting loratadine for my pollen allergies, it works but I get very drowsy in the afternoon (even though I take it in the morning). It's so bad that I have trouble concentrating on my work.

I've read that loratadine is supposed to be the antihistamine that don't make you drowsy and that cetirizine is actually worse. Is there any use for me to try it anyway to see if it's better?

Antihistamines in order of least to worst sedating:
Loratadine
Fexofenadine
Cetirizine
Benadryl

People are different, so you may not find Cetirizine sedating.

Have you tried something like a nasal steroid spray? This can be just as effective, with fewer side effects.

What are the side effects of taking Loratadine?, I took it for my allergies of course, but I took it on an empty stomach. Exactly 24 hours after I took it, I was extremely drowsy and weak. Oh, my stomach also made gurgling noises all day. Is it possible that these are related to taking Loratadine?

[That's generic claritin btw]

The stomach stuff, definitely. I grab at least a piece of toast and a bottle of water in the morning now, just to stop that. The weakness, I have heard of, my mom got it when she first started on it but it stopped after the second week. I haven't heard of a lot of drowsiness though. Maybe the dehydration caused that?

What is the recommended dose of claritin (loratadine) for a dog?, Pooch has skin allergies. I plan to try benadryl, but would rather use claritin due to its lack of a sedating effect.

I have the same problem with my dog. Whenever the allergies would flare up it would affect his ears and belly. I actually found that changing his food (he was on hypo-allergenic dog food) to a lamb and rice based food (instead of beef flavor) cleared up the reaction. Every once in a while I give him a benadryl if he has an exceptionally bad reaction. The dosage depends on the size, weight and the severity of the skin allergy. I'd call your Vet and ask them for dosage amounts.

Does loratadine work with itches caused by allergic reactions?, I bought loratadine Because i was told benadryl(in pill form) was good for this. I bought it because i know benadryl knocks me out. i figured i'd try loratadine instead(it still knocks me out) I seem to not be itching but could that be the reason or is it just that i'm not itching at this time. Itch creams don't work. I've had this itch for months. I'm hoping this is gonna help because this itch is driving me crazy.

take the med as directed, drink lotsa water, and follow up with your doctor.

What happens when you take a double dose of loratadine/claritin?, They say don't take two doses, but one doesn't normally work too well and I can't afford a doctor to ask. Anyone had any experiences?

The answer to that depends on whether your dose is prescription strength or over the counter strength. The answer also depends on your weight. If you are over 200 pounds, sometimes 2 tablets is really the effective dose. While homeboy above me is mostly correct, he is not totally correct. They also have to make sure the dose is safe for 12 year olds that weigh 100 pounds to get the correct labeling. And while there are only a certain number of sites (correct), taking more increases the odds that those receptors remain blocked from the effects of histamine. Risks of taking too much (overdose levels) include liver and kidney issues.

Let's ask Mr. Pharmacologist to read a little about the clinical trials and comments from the FDA (link attached).

You may want to consider another third generation H1 antagonist like Zyrtec. Zyrtec is now offered over the counter. This medication has a greater affinity for the H1 (histamine) receptor and is typically more effective than Claritin. Some populations find that Zyrtec works but it makes them a little drowsy. For some, drowsy is a lot better than snotty, sneezy, wheezy, and miserable.