Riik: Ameerika Ühendriigid
keel: inglise
Allikas: NLM (National Library of Medicine)
THEOPHYLLINE ANHYDROUS (UNII: 0I55128JYK) (THEOPHYLLINE ANHYDROUS - UNII:0I55128JYK)
Major Pharmaceuticals
THEOPHYLLINE ANHYDROUS
THEOPHYLLINE ANHYDROUS 100 mg
PRESCRIPTION DRUG
Abbreviated New Drug Application
THEOPHYLLINE- THEOPHYLLINE TABLET, EXTENDED RELEASE MAJOR PHARMACEUTICALS ---------- THEOPHYLLINE EXTENDED-RELEASE TABLETS DESCRIPTION Theophylline is structurally classified as a methylxanthine. It occurs as a white, odorless, crystalline powder with a bitter taste. Anhydrous theophylline has the chemical name 1H-Purine-2,6-dione,3,7- dihydro-1,3-dimethyl-, and is represented by the following structural formula: C H N O M.W. 180.17 This product allows a 12-hour dosing interval for a majority of patients and a 24-hour dosing interval for selected patients (see DOSAGE AND ADMINISTRATION section for description of appropriate patient populations). Each extended-release tablet for oral administration contains either 100 mg, 200 mg, 300 mg or 450 mg of anhydrous theophylline. Tablets also contain as inactive ingredients: hypromellose, anhydrous lactose, magnesium stearate and povidone. CLINICAL PHARMACOLOGY MECHANISM OF ACTION Theophylline has two distinct actions in the airways of patients with reversible obstruction; smooth muscle relaxation (i.e., bronchodilation) and suppression of the response of the airways to stimuli (i.e., non-bronchodilator prophylactic effects). While the mechanisms of action of theophylline are not known with certainty, studies in animals suggest that bronchodilatation is mediated by the inhibition of two isozymes of phosphodiesterase (PDE lll and, to a lesser extent, PDE IV) while non-bronchodilator prophylactic actions are probably mediated through one or more different molecular mechanisms, that do not involve inhibition of PDE lll or antagonism of adenosine receptors. Some of the adverse effects associated with theophylline appear to be mediated by inhibition of PDE lll (e.g., hypotension, tachycardia, headache, and emesis) and adenosine receptor antagonism (e.g., alterations in cerebral blood flow). Theophylline increases the force of contraction of diaphragmatic muscles. This action appears to be due to enhancement of calcium uptake through an adenosine-mediated channel. SERUM CONCEN Lugege kogu dokumenti