Allegra-D 24 Hour
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Allegra-D 24 Hour
ALLEGRA-D®24 HOUR (fexofenadine HCl 180 mg and pseudoephedrine HCl 240 mg) Extended-Release Tablets
DRUG DESCRIPTION
ALLEGRA-D® 24 HOUR (fexofenadine hydrochloride and pseudoephedrine hydrochloride) Extended-Release Tablets for oral administration contain 180 mg fexofenadine hydrochloride for immediate release and 240 mg pseudoephedrine hydrochloride for extended release. Tablets also contain as excipients: microcrystalline cellulose, sodium chloride, cellulose acetate, polyethylene glycol, opadry white, povidone, talc, hypromellose, croscarmellose sodium, copovidone, titanium dioxide, magnesium stearate, colloidal silicon dioxide, brilliant blue aluminum lake, acetone, isopropyl alcohol, methyl alcohol, methylene chloride, water, and black ink.
Fexofenadine hydrochloride, one of the active ingredients of ALLEGRA-D 24 HOUR (fexofenadine hcl 180 and pseudoephendrine hcl 240) , is a histamine H1-receptor antagonist with the chemical name (±)-4-[1-hydroxy-4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-butyl]-α, α-dimethyl benzeneacetic acid hydrochloride and the following chemical structure:
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The molecular weight is 538.13 and the empirical formula is C32H39NO4•HCl. Fexofenadine hydrochloride is a white to off-white crystalline powder. It is freely soluble in methanol and ethanol, slightly soluble in chloroform and water, and insoluble in hexane. Fexofenadine hydrochloride is a racemate and exists as a zwitterion in aqueous media at physiological pH.
Pseudoephedrine hydrochloride, the other active ingredient of ALLEGRA-D 24 HOUR, is an adrenergic (vasoconstrictor) agent with the chemical name [S-(R*,R*)]-α-[1-(methylamino)ethyl]-benzenemethanol hydrochloride and the following chemical structure:
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The molecular weight is 201.70 and the molecular formula is C10H15NO•HCl. Pseudoephedrine hydrochloride occurs as fine, white to off-white crystals or powder, having a faint characteristic odor. It is very soluble in water, freely soluble in alcohol, and sparingly soluble in chloroform.
What are the possible side effects of fexofenadine and pseudoephedrine (Allegra-D 12 Hour, Allegra-D 24 Hour)?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Stop using this medication and call your doctor at once if you have a serious side effect such as:
- fast, pounding, or uneven heartbeat;
- confusion, hallucinations, unusual thoughts or behavior;
- severe dizziness, anxiety, restless feeling, or nervousness;
- increased blood pressure (severe headache, blurred vision, trouble concentrating,...
Read All Potential Side Effects and See Pictures of Allegra-D 24 Hour »
What are the precautions when taking fexofenadine hcl 180 and pseudoephendrine hcl 240 (Allegra-D 24 Hour)?
Before taking this medication, tell your doctor or pharmacist if you are allergic to fexofenadine or pseudoephedrine; or if you have any other allergies. Also, tell your doctor if you have had serious side effects from similar medications (such as other decongestants, including phenylephrine). This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: glaucoma, difficulty urinating (such as due to an enlarged prostate), high blood pressure (hypertension), heart/blood vessel disease (such as coronary artery disease), overactive thyroid (hyperthyroidism), diabetes, kidney disease.
This drug may...
Last reviewed on RxList: 5/10/2010
This monograph has been modified to include the generic and brand name in many instances.
Additional Allegra-D 24 Hour Information
Allegra-D 24 Hour - User Reviews
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