Allegra

Antihistamines are known for their sedative effects. However, some studies suggested mild stimulant effects in the case of fexofenadine. The goals of this study are to examine whether fexofenadine possesses stimulating properties and to determine whether such stimulating effects are related to workload. Sixteen healthy volunteers received a single dose of 180 and 360 mg fexofenadine and placebo on separate test days. Drug effects were assessed using a divided attention task (DAT), continuous performance task (CPT) and motor choice reaction time test (MCRT). Sensitivity of the tasks was increased by manipulating the workload during task performance. Event Related brain Potentials (ERPs) were measured in the DAT and CPT to study the underlying neurophysiological processes. An interaction effect of Treatment and Workload was found on tracking performance in the DAT and on movement time in the MCRT. Performance on the DAT was less affected by increments in workload after fexofenadine as compared to placebo. P1 and P3 latency were affected by Treatment x Workload and Treatment respectively and indicated faster attentional and information processing latencies following fexofenadine treatment. Treatment did not influence performance in the CPT task or in the ERPs measured during this task. The MCRT demonstrated faster movement times following fexofenadine treatment. These results suggest that although the neurophysiological data indicate central nervous system (CNS) activation after fexofenadine treatment, the magnitude of the centrally activating effects is too small to produce relevant performance improvement at the behavioural level.

Allergies are easy to treat for many children, they simply take an allergy medication, such as Allegra (fexofenadine), Claritin (loratadine), Singulair (montelukast), or Zyrtec (cetirizine), and their allergy symptoms get under easy control.

Other children have more hard-to-control allergies though, and suffer either with their allergy symptoms or try many different allergy medicines without relief. It is much better to get help to learn treat your child’s allergies more effectively.

Human histamine skin wheal and flare studies following single and twice daily doses of 20 and 40 mg Fexofenadine hydrochloride demonstrated that the drug exhibits an antihistamine effect by 1 hour, achieves maximum effect at 2 to 3 hours, and an effect is still seen at 12 hours. There was no evidence of tolerance to these effects after 28 days of dosing. The clinical significance of these observations is unknown.

Histamine skin wheal and flare studies in 7 to 12 year old subjects showed that following a single dose of 30 or 60 mg, antihistamine effect was observed at 1 hour and reached a maximum by 3 hours. Greater than 49% inhibition of wheal area, and 74% inhibition of flare area were maintained for 8 hours following the 30 and 60 mg dose.

Pharmacokinetics in special populations (for renal, hepatic impairment, and age), obtained after a single dose of 80 mg Fexofenadine hydrochloride, were compared to those from healthy volunteers in a separate study of similar design.

Geriatric Subjects

In older subjects (≥65 years old), peak plasma levels of Fexofenadine were 99% greater than those observed in younger subjects (<65 years old). Mean Fexofenadine elimination half-lives were similar to those observed in younger subjects.

Pediatric Subjects

Cross study comparisons indicated that Fexofenadine area under the curve (AUC) following oral administration of a 60 mg dose of Fexofenadine hydrochloride to 7–12 year old pediatric subjects with allergic rhinitis was 56% greater compared to healthy adult volunteers given the same dose. Plasma exposure in pediatric subjects given 30 mg Fexofenadine hydrochloride is comparable to adults given 60 mg.

Renally Impaired

In subjects with mild to moderate (creatinine clearance 41–80 mL/min) and severe (creatinine clearance 11–40 mL/min) renal impairment, peak plasma levels of Fexofenadine were 87% and 111% greater, respectively, and mean elimination half-lives were 59% and 72% longer, respectively, than observed in healthy volunteers. Peak plasma levels in subjects on dialysis (creatinine clearance ≤10 mL/min) were 82% greater and half-life was 31% longer than observed in healthy volunteers. Based on increases in bioavailability and half-life, a dose of 60 mg once daily is recommended as the starting dose in patients with decreased renal function. (See DOSAGE AND ADMINISTRATION).

Hepatically Impaired

The pharmacokinetics of Fexofenadine in subjects with hepatic disease did not differ substantially from that observed in healthy volunteers.

Effect of Gender

Across several trials, no clinically significant gender-related differences were observed in the pharmacokinetics of Fexofenadine hydrochloride.

Fexofenadine hydrochloride was rapidly absorbed following oral administration of a single dose of two 60 mg capsules to healthy male volunteers with a mean time to maximum plasma concentration occurring at 2.6 hours post-dose. After administration of a single 60 mg capsule to healthy volunteers, the mean maximum plasma concentration was 131 ng/mL. Following single dose oral administrations of either the 60 and 180 mg tablet to healthy adult male volunteers, mean maximum plasma concentrations were 142 and 494 ng/mL, respectively. The tablet formulations are bioequivalent to the capsule when administered at equal doses. Fexofenadine hydrochloride pharmacokinetics are linear for oral doses up to a total daily dose of 240 mg (120 mg twice daily). The administration of the 60 mg capsule contents mixed with applesauce did not have a significant effect on the pharmacokinetics of Fexofenadine in adults.

Co-administration of 180 mg Fexofenadine hydrochloride tablet with a high fat meal decreased the AUC and Cmax of Fexofenadine by 21 and 20% respectively.

Fruit juices such as grapefruit, orange and apple may reduce the bioavailability and exposure of fexofenadine. This is based on the results from 3 clinical studies using histamine induced skin wheals and flares coupled with population pharmacokinetic analysis. The size of wheal and flare were significantly larger when fexofenadine hydrochloride was administered with either grapefruit or orange juices compared to water. Based on the literature reports, the same effects may be extrapolated to other fruit juices such as apple juice. The clinical significance of these observations is unknown. In addition, based on the population pharmacokinetics analysis of the combined data from grapefruit and orange juices studies with the data from a bioequivalence study, the bioavailability of fexofenadine was reduced by 36%. Therefore, to maximize the effects of fexofenadine, it is recommended that ALLEGRA tablets should be taken with water (see Pharmacokinetics and DOSAGE AND ADMINISTRATION).

Overall rating 

Effectiveness:          Highly Effective
Side effects:          No Side Effects

Treatment Info

Condition / reason:          Allergies
Dosage & duration:          60 mg taken twice per day for the period of 2 years
Other conditions:          Ocular hypertension
Other drugs taken:          Xalatan

Reported Results

Benefits:          This drug alleviates my allergic responses–itchy eyes and sneezing. It’s effective because if I don’t use it, my symptoms return.
Side effects:          I’m not sure if this drug has a drying effect. I don’t think so, but I really don’t know how to tell.
Comments:          I take a pill approximately every 12 hours. I try to keep well hydrated.

The safety of fexofenadine has been examined extensively in adults and school-age children. However, the safety of fexofenadine in children younger than 6 years has not been reported to date. OBJECTIVE: To compare the safety and tolerability of twice-daily fexofenadine hydrochloride, 30 mg, and placebo in preschool children aged 2 to 5 years with allergic rhinitis. METHODS: This was a multicenter, double-blind, randomized, placebo-controlled, parallel-group study, conducted between February 29, 2000, and June 14, 2001. Participants were randomized to either fexofenadine hydrochloride, 30 mg, or placebo twice daily for a 2-week period. To facilitate dosing, capsule content was mixed with applesauce (approximately 10 mL). Safety assessments depended on date of entry into the study because of an amendment to the protocol. Before the amendment, assessments included physical examination, vital signs reporting (oral temperature, heart rate, and respiratory rate), and adverse event (AE) reporting. After the amendment, safety assessments included laboratory testing (blood chemistry and hematology profiles), physical examination, 12-lead electrocardiography, and vital signs (oral temperature, blood pressure, heart rate, and respiratory rate) and AE reporting. RESULTS: Treatment-emergent AEs were observed in 116 of 231 participants receiving placebo and 111 of 222 receiving fexofenadine. These AEs were possibly related to study medication in 19 (8.2%) and 21 (9.5%) of the participants receiving placebo and fexofenadine, respectively, and most frequently involved the digestive system. No clinically relevant differences in laboratory measures, vital signs, and physical examinations were observed. CONCLUSIONS: The findings show that fexofenadine hydrochloride, 30 mg, is well tolerated and has a good safety profile in children aged 2 to 5 years with allergic rhinitis.

• If you have any questions about Allegra , please talk with your doctor, pharmacist, or other health care provider.
• Allegra is to be used only by the patient for whom it is prescribed. Do not share it with other people.
• Carry an identification card at all times that says you are taking Allegra .

This information is a summary only. It does not contain all information about Allegra . If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

• Allegra may cause dizziness. It does not usually cause drowsiness when used under normal circumstances at the recommended doses. However, these effects may be worse if you take Allegra with alcohol or certain medicines. Use Allegra with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
• Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
• Allegra may interfere with skin allergy tests. If you are scheduled for a skin test, talk to your doctor. You may need to stop taking Allegra for a few days before the tests.
• Use Allegra with caution in the ELDERLY; they may be more sensitive to its effects.
• Allegra should be used with extreme caution in CHILDREN younger than 6 months old; safety and effectiveness in these children have not been confirmed.
• PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Allegra while you are pregnant. It is not known if Allegra is found in breast milk. If you are or will be breast-feeding while you use Allegra , check with your doctor. Discuss any possible risks to your baby.