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Allegra and/or Equivalents

Drug Related Drug Names
Allegra 60mg and/or Equivalents Allegra 12 Hour, Telfast
Allegra 120mg and/or Equivalents Allegra 24 hour, Fexofenadine, Telfast
Allegra 180mg and/or Equivalents Fexofenadine, Telfast

Allegra (fexofenadine)

Allegra Drug Description

Allegra is an H1 antihistamine known for its rapid and prolonged anti-allergic action. As a hydrochloride compound, it is used to treat hay fever and allergic rhinitis, and also in the treatment of chronic urticaria. Allegra was developed by the Sanofi-Aventis laboratory as a successor and replacement of terfenadine, an antihistamine with near-fatal cardiac side effects.

Allegra, as many antihistamines, is used as a racemate (a combination of equivalent amounts of two enantiomorphs). Allegra is synthesized from piperidine-4-carboxylate and 4-bromophenyl acetonitrile compounds. First both the compounds are introduced as phenyl esters via a Grignard reaction. The amino group is then reacted with the protected aldehyde 2 - (4'-bromobutyl)-dioxolane (an acetal), and the alkyl protecting group is then removed with acid. The other part of Allegra is synthesized by double alkylation of the nitrile derived carbanion with iodomethane. The nitrile group is now the hydrolyzed form of carboxylic acid. The aryl bromide is then removed by lithiation with n-butyllithium and organolithium compounds. This reaction leads to the formation of Allegra.

Allegra is rapidly absorbed after oral intake, and after about 2 hours maximum plasma levels are reached. The bioavailability is not known. 80% Allegra in the body is excreted in the feces. About 10% of the dose is found in urine. According to company information, the plasma half-life is averaged 13 hours per dosage. Allegra is used as a third-generation antihistamine for hay fever and similar allergic symptoms. It reduces allergic symptoms such as displacement of histamine from the H1 receptor.

Allegra was introduced as a substitute of terfenadine which had to be eliminated from the market because of serious side effects. This metabolite has the same biological activity as terfenadine, but causes very fewer side effects. They have no anticholinergic or alpha-receptor blocking action. In contrast to terfenadine, Allegra does not block the potassium channels in animal heart muscle cells. Allegra was developed by Sepracor and approved in the United States in 1996. The patents for the production of Allegra and its intermediate products are held by the French medical pharmaceutical company, Sanofi-Aventis and Albany Molecular Research Inc. (AMRI).

Conditions Treated by Allegra

Seasonal allergic rhinitis

In a double-blind multicenter study, 570 subjects with a seasonal allergic rhinitis received two weeks of Allegra or placebo. Different doses of Allegra (60, 120 or 240 mg) or placebo were given twice daily. The assessment of the effect was made by the patients using a symptom scale in the evening, 12 hours after taking the medication. All Allegra doses compared to placebo resulted in a significant reduction of symptoms (overall and for individual nasal symptoms). The higher doses were not more effective than the lowest dose (60 mg 2 times per day).

Another two-week double-blind study was carried out with 588 people who also had allergic rhinitis. The Allegra dose here was 40 to 120 mg twice daily. Again in this study, the mentioned symptom scale used showed a significantly better effect than placebo. Normal Allegra dose (120 or 180 mg once a day) in a placebo-controlled comparison with cetirizine (10 mg per day) was used. 821 people with seasonal allergic rhinitis were tested to assess the effect according to a scale of symptoms evaluated over a 24-hour period. The two doses of Allegra and cetirizine were significantly more effective than placebo.


In an unpublished double-blind study, 224 subjects with chronic idiopathic urticaria were evaluated for two weeks, with daily with doses of Allegra or placebo. Four different doses of Allegra between 60-240 mg were used. This active treatment resulted in a significant reduction in pruritus and lower impairment of daytime activities and nighttime sleep. According to the rating scale, the two higher daily doses (180 or 240 mg) were significantly more effective than placebo.

Allegra Dosage Information

a) Typical Dosage Recommendations

The average dosage is 120 mg per day. Allegra are available as tablets, ranging from 60 mg to 180 mg. The drug requires a prescription from an authorized doctor or physician. In case of seasonal allergic rhinitis, you are advised to take a 120 mg dose daily and for urticaria you should take a 180 mg dose. Children under the age of 12, and pregnant and lactating women should not take any Allegra doses. In individuals with impaired renal function, it is recommended to reduce the dose of Allegra and to double the dosage interval. There is general recommendation for dose reduction in older people.

b) Missing a Dose

Skipping a dose generally does not have any medical repercussions. So if you miss a dose and realize it later on, don’t hastily take that dose just minutes you are supposed to take the next one.

c) Overdosing

The symptoms of an overdose are hardly known because overdose reports are rare. Mice were tested with dosages around 400 times higher than that of a normal human dosage and were unaffected. Studies in humans with a single dose of 800 mg per day with up to two 690 mg daily doses over a period of one month, showed no noteworthy undesirable clinical effects, in comparison with a placebo.

Allegra Side Effects

In previously conducted clinical trials, people treated with Allegra had no more adverse effects than those receiving placebo. According to the manufacturer, just over 1% of 2461 patients complained of:

These symptoms were often similar to those treated with placebo. Only flu-like infections (2.5%) and dysmenorrhea (1.5%) were observed in the actively treated patients, but a connection with Allegra seems unlikely. Like most H1 antihistamines of today, it overcomes only a small part of the blood-brain barrier. Therefore, Allegra has a relatively low sedative effect.

Rare side effects include:

Possible Drug Interactions With Allegra

In controlled clinical studies, no interactions were observed with other drugs, and therefore there was no influence on the safety and effectiveness of Allegra. Healthy subjects, whose plasma levels of Allegra (taking 120 mg 2 times each day) were steady in receiving additional Erythromycin Base(500 mg 3 times each day) or Nizoral 400mg (ketoconazole) (400 mg each day).

If you have any questions about buying discount Allegra online or any other prescription products you can contact our team of professional Patient Service Representatives or one of our pharmacists 24-7 by calling 1-800-226-3784.

Notice: The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Allegra and/or Equivalents warnings, side-effects and general information