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Controlled and uncontrolled clinical trials conducted in the United States and Canada included more than 6000 patients aged 12 years and older, with more than 3900 receiving ZYRTEC (cetirizine) at doses of 5 to 20 mg per day. The duration of treatment ranged from 1 week to 6 months, with a mean exposure of 30 days.
Most adverse reactions reported during therapy with ZYRTEC (cetirizine) were mild or moderate. In placebo-controlled trials, the incidence of discontinuations due to adverse reactions in patients receiving ZYRTEC (cetirizine) 5 or 10 mg was not significantly different from placebo (2.9% vs. 2.4%, respectively).
The most common adverse reaction in patients aged 12 years and older that occurred more frequently on ZYRTEC (cetirizine) than placebo was somnolence. The incidence of somnolence associated with ZYRTEC (cetirizine) was dose related, 6% in placebo, 11% at 5 mg and 14% at 10 mg. Discontinuations due to somnolence for ZYRTEC (cetirizine) were uncommon (1.0% on ZYRTEC (cetirizine) vs. 0.6% on placebo). Fatigue and dry mouth also appeared to be treatment-related adverse reactions. There were no differences by age, race, gender or by body weight with regard to the incidence of adverse reactions.
Table 1 lists adverse experiences in patients aged 12 years and older which were reported for ZYRTEC (cetirizine) 5 and 10 mg in controlled clinical trials in the United States and that were more common with ZYRTEC (cetirizine) than placebo.
Adverse Experiences Reported in Patients Aged 12 Years and Older in
Placebo-Controlled United States ZYRTEC (cetirizine) Trials (Maximum Dose of 10 mg)
at Rates of 2% or Greater (Percent Incidence)
|Adverse Experience|| ZYRTEC
In addition, headache and nausea occurred in more than 2% of the patients, but were more common in placebo patients.
Pediatric studies were also conducted with ZYRTEC (cetirizine) . More than 1300 pediatric patients aged 6 to 11 years with more than 900 treated with ZYRTEC (cetirizine) at doses of 1.25 to 10 mg per day were included in controlled and uncontrolled clinical trials conducted in the United States. The duration of treatment ranged from 2 to 12 weeks. Placebo-controlled trials up to 4 weeks duration included 168 pediatric patients aged 2 to 5 years who received cetirizine, the majority of whom received single daily doses of 5 mg. A placebo-controlled trial 18 months in duration included 399 patients aged 12 to 24 months treated with cetirizine (0.25 mg/kg bid), and another placebo-controlled trial of 7 days duration included 42 patients aged 6 to 11 months who were treated with cetirizine (0.25 mg/kg bid).
The majority of adverse reactions reported in pediatric patients aged 2 to 11 years with ZYRTEC (cetirizine) were mild or moderate. In placebo-controlled trials, the incidence of discontinuations due to adverse reactions in pediatric patients receiving up to 10 mg of ZYRTEC (cetirizine) was uncommon (0.4% on ZYRTEC (cetirizine) vs. 1.0% on placebo).
Table 2 lists adverse experiences which were reported for ZYRTEC (cetirizine) 5 and 10 mg in pediatric patients aged 6 to 11 years in placebo-controlled clinical trials in the United States and were more common with ZYRTEC (cetirizine) than placebo. Of these, abdominal pain was considered treatment-related and somnolence appeared to be dose-related, 1.3% in placebo, 1.9% at 5 mg and 4.2% at 10 mg. The adverse experiences reported in pediatric patients aged 2 to 5 years in placebo-controlled trials were qualitatively similar in nature and generally similar in frequency to those reported in trials with children aged 6 to 11 years.
In the placebo-controlled trials of pediatric patients 6 to 24 months of age, the incidences of adverse experiences were similar in the cetirizine and placebo treatment groups in each study. Somnolence occurred with essentially the same frequency in patients who received cetirizine and patients who received placebo. In a study of 1 week duration in children 6-11 months of age, patients who received cetirizine exhibited greater irritability/fussiness than patients on placebo. In a study of 18 months duration in patients 12 months and older, insomnia occurred more frequently in patients who received cetirizine compared to patients who received placebo (9.0% v. 5.3%). In those patients who received 5 mg or more per day of cetirizine as compared to patients who received placebo, fatigue (3.6% v. 1.3%) and malaise (3.6% v. 1.8%) occurred more frequently.
Adverse Experiences Reported in Pediatric Patients Aged 6 to 11 Years in Placebo-Controlled United States ZYRTEC (cetirizine) Trials (5 or 10 mg Dose) Which Occurred at a Frequency of =2% in Either the 5-mg or the 10-mg ZYRTEC (cetirizine) Group, and More Frequently< Than in the Placebo Group
|Adverse Experiences|| Placebo
| 5 mg
| 10 mg
The following events were observed infrequently (less than 2%), in either 3982 adults and children 12 years and older or in 659 pediatric patients aged 6 to 11 years who received ZYRTEC (cetirizine) in U.S. trials, including an open adult study of six months duration. A causal relationship of these infrequent events with ZYRTEC (cetirizine) administration has not been established.
Central and Peripheral Nervous Systems: abnormal coordination, ataxia, confusion, dysphonia, hyperesthesia, hyperkinesia, hypertonia, hypoesthesia, leg cramps, migraine, myelitis, paralysis, paresthesia, ptosis, syncope, tremor, twitching, vertigo, visual field defect.
Gastrointestinal: abnormal hepatic function, aggravated tooth caries, constipation, dyspepsia, eructation, flatulence, gastritis, hemorrhoids, increased appetite, melena, rectal hemorrhage, stomatitis including ulcerative stomatitis, tongue discoloration, tongue edema.
Psychiatric: abnormal thinking, agitation, amnesia, anxiety, decreased libido, depersonalization, depression, emotional lability, euphoria, impaired concentration, insomnia, nervousness, paroniria, sleep disorder.
Skin: acne, alopecia, angioedema, bullous eruption, dermatitis, dry skin, eczema, erythematous rash, furunculosis, hyperkeratosis, hypertrichosis, increased sweating, maculopapular rash, photosensitivity reaction, photosensitivity toxic reaction, pruritus, purpura, rash, seborrhea, skin disorder, skin nodule, urticaria.
Special Senses: parosmia, taste loss, taste perversion.
Body as a Whole: accidental injury, asthenia, back pain, chest pain, enlarged abdomen, face edema, fever, generalized edema, hot flashes, increased weight, leg edema, malaise, nasal polyp, pain, pallor, periorbital edema, peripheral edema, rigors.
Occasional instances of transient, reversible hepatic transaminase elevations have occurred during cetirizine therapy. Hepatitis with significant transaminase elevation and elevated bilirubin in association with the use of ZYRTEC (cetirizine) has been reported.
In the post-marketing period, the following additional rare, but potentially severe adverse events have been reported: aggressive reaction, anaphylaxis, cholestasis, convulsions, glomerulonephritis, hallucinations, hemolytic anemia, hepatitis, orofacial dyskinesia, severe hypotension, stillbirth, suicidal ideation, suicide and thrombocytopenia.
Drug Abuse And Dependence
There is no information to indicate that abuse or dependency occurs with ZYRTEC (cetirizine) .
Read the Zyrtec (cetirizine) Side Effects Center for a complete guide to possible side effects
Drug-Drug Interactions: No clinically significant drug interactions have been found with theophylline at a low dose, azithromycin, pseudoephedrine, ketoconazole, or erythromycin. There was a small decrease in the clearance of cetirizine caused by a 400-mg dose of theophylline; it is possible that larger theophylline doses could have a greater effect.
Read the Zyrtec Drug Interactions Center for a complete guide to possible interactions
Last reviewed on RxList: 5/16/2007
This monograph has been modified to include the generic and brand name in many instances.
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