Theophylline
Theophylline
Rebirthing
<catset>Category="Bronchodilators"</catset><catset>Category="Xanthines"</catset><right><p><table border=1 cellpadding=3 cellspacing=0 width=250 style=" border-collapse: collapse; margin: 0 0 0 0.5em"><tr><td bgcolor=ffffff align=center colspan=2> [image]<br><i>Theophylline</i></td></tr><tr><td align=center colspan=2><i>3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione (or 1,3-dimethylxanthine)</i></td></tr><tr align=center style=" border-bottom: 3px solid gray"><td><b><a href="CAS registry number">CAS number</a></b><br>58-55-9</td><td><b><a href="Anatomical Therapeutic Chemical Classification System">ATC code</a></b><br>R03DA04</td></tr><tr><td bgcolor=eeeeee><a href="Chemical formula">Chemical formula</a></td><td bgcolor=ddeeff><a href="Carbon">C</a><sub>7</sub><a href="Hydrogen">H</a><sub>8</sub><a href="Nitrogen">N</a><sub>4</sub><a href="Oxygen">O</a><sub>2</sub></td></tr><tr><td bgcolor=eeeeee><a href="Molecular mass">Molecular weight</a></td><td bgcolor=ddeeff>180.16 <a href="Atomic mass unit">Da</a></td></tr><tr><td bgcolor=eeeeee><a href="Bioavailability">Bioavailability</a></td><td bgcolor=ddeeff>?</td></tr><tr><td bgcolor=eeeeee>Metabolism</td><td bgcolor=ddeeff>?</td></tr><tr><td bgcolor=eeeeee><a href="Half-life">Elimination half life</a></td><td bgcolor=ddeeff>?</td></tr><tr><td bgcolor=eeeeee><a href="Excretion">Excretion</a></td><td bgcolor=ddeeff>?</td></tr><tr><td bgcolor=eeeeee><a href="Pregnancy category">Pregnancy category</a> </td><td bgcolor=ddeeff><a href="Australia">Australia</a>: A<br><a href="Usa, Oita">USA</a>: C</td></tr><tr><td bgcolor=eeeeee><a href="Controlled Substances Act">Legal status</a></td><td bgcolor=ddeeff>N/A</td></tr><tr><td bgcolor=eeeeee>Delivery</td><td bgcolor=ddeeff>?</td></tr></table><p></right> <b>Theophylline</b> is a <a href="Xanthine">methylxanthine</a> drug and is used in therapy for respiratory diseases, under a variety of brand names. It bears structural and pharmacological similarity to <a href="Caffeine">Caffeine</a>. It is naturally found in <a href="Black tea">Black tea</a> and <a href="Green tea">Green tea</a>.<p>The main actions of theophylline are: <ul> <li> relaxation of bronchial <a href="Smooth muscle">Smooth muscle</a> <li> positive <a href="Inotrope">inotropic</a> (increases heart muscle contractility and efficiency) <li> positive <a href="Chronotropic">Chronotropic</a> (increases heart rate) <li> lowers <a href="Blood pressure">Blood pressure</a> <li> increases <a href="Kidney">renal</a> blood flow <li> some <a href="Inflammation">anti-inflammatory</a> effect </ul><p>The use of theophylline is complicated by the fact that it interacts with various drugs, chiefly <a href="Cimetidine">Cimetidine</a> and <a href="Phenytoin">Phenytoin</a>, and that it has a narrow <a href="Therapeutic index">Therapeutic index</a>, so its use must be monitored to avoid toxicity. It can also cause nausea, diarrh&#339;a, increase in heart rate, arrhythmias and CNS excitation. Its toxicity is increased by erythromycin, cimetidine and fluoroquinolones.<p>The main therapeutic uses of theophylline are: <ul> <li> chronic obstructive diseases of the airways <ul> <li> chronic obstructive pulmonary disease <a href="Chronic obstructive pulmonary disease">COPD</a> <li> <a href="Asthma">bronchial asthma</a> </ul> </ul><p>Proposed mechanism of action include a non-specific inhibition of the enzyme phosphodiesterase, producing an increase in intracellular cyclic AMP, however this is not known with certainty.<font color=#700070></font><font color=#700070></font><font color=#700070></font><p>[image]