Zanaflex
Zanaflex Capsules™
(tizanidine hydrochloride)
Zanaflex® Tablets
(tizanidine hydrochloride)
PHARMACOKINETIC DIFFERENCES BETWEEN Zanaflex Capsules™AND ZANAFLEX® TABLETS:
Zanaflex Capsules™ARE NOT BIOEQUIVALENT TO ZANAFLEX® TABLETS IN THE FED STATE. THE PRESCRIBER SHOULD BE THOROUGHLY FAMILIAR WITH THE COMPLEX EFFECTS OF FOOD ON TIZANIDINE PHARMACOKINETICS (see PHARMACOKINETICS and DOSAGE AND ADMINISTRATION).
DRUG DESCRIPTION
Zanaflex® (tizanidine hydrochloride) is a centrally acting α2-adrenergic agonist. Tizanidine HCl (tizanidine) is a white to off-white, fine crystalline powder, which is odorless or with a faint characteristic odor. Tizanidine is slightly soluble in water and methanol; solubility in water decreases as the pH increases. Its chemical name is 5-chloro-4-(2-imidazolin-2-ylamino)-2,1,3-benzothiodiazole hydrochloride. Tizanidine's molecular formula is C9H8CIN5 S-HCl, its molecular weight is 290.2 and its structural formula is:
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Zanaflex Capsules™ are supplied as 2, 4, and 6 mg capsules and Zanaflex®
tablets are supplied as 2 and 4 mg tablets for oral administration. Zanaflex Capsules™ are composed of the active ingredient, tizanidine hydrochloride
(2.29 mg equivalent to 2 mg tizanidine base, 4.58 mg equivalent to 4 mg tizanidine
base, and 6.87 mg equivalent to 6 mg tizanidine base), and the inactive ingredients,
hydroxypropyl methyl cellulose, silicon dioxide, sugar spheres, titanium dioxide,
gelatin, and colorants.
Zanaflex® tablets are composed of the active ingredient, tizanidine hydrochloride (2.29 mg equivalent to 2 mg tizanidine base and 4.58 mg equivalent to 4 mg tizanidine base), and the inactive ingredients, silicon dioxide colloidal, stearic acid, microcrystalline cellulose and anhydrous lactose.
Generic Name: Tizanidine
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