Doxofylline is a novel, selective xanthine derivative bronchodilator used primarily in the management of chronic obstructive pulmonary disease (COPD) and bronchial asthma. It is a methylxanthine derivative with a dioxolane group at position 7, which confers a distinct pharmacological profile compared to theophylline. It is known for its bronchodilatory and anti-inflammatory effects with a potentially improved safety and tolerability profile, particularly a lower incidence of central nervous system and cardiovascular side effects.
Adult: 400 mg orally twice daily (every 12 hours). The maintenance dose can range from 400 mg to 800 mg per day in divided doses.
Note: Tablet should be swallowed whole with a full glass of water, with or without food. To minimize gastric upset, it can be taken after meals. Do not crush or chew sustained-release formulations if available. Maintain consistent timing of doses.
Doxofylline acts as a bronchodilator and possesses anti-inflammatory properties. Its primary mechanism is non-selective inhibition of phosphodiesterase (PDE) enzymes, particularly PDE III and PDE IV, leading to an increase in intracellular cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) in bronchial smooth muscle cells and inflammatory cells. Elevated cAMP causes relaxation of bronchial smooth muscle. Unlike theophylline, it has very low antagonistic activity on adenosine receptors (A1 and A2).
Pregnancy: Category C: Animal studies have shown adverse effects. There are no adequate and well-controlled studies in pregnant women. Use only if the potential benefit justifies the potential risk to the fetus.
Driving: May cause dizziness, nervousness, or visual disturbances. Patients should be cautioned about operating machinery or driving until they know how the drug affects them.
| Ciprofloxacin, Enoxacin | May increase doxofylline levels by inhibiting its metabolism. Risk of toxicity. | Major |
| Erythromycin, Clarithromycin | May increase doxofylline levels. Monitor for side effects. | Moderate |
| Allopurinol | May increase doxofylline levels. | Moderate |
| Beta-2 Agonists (Salbutamol, Formoterol) | Additive bronchodilatory effect; may potentiate hypokalemia and tachycardia. | Moderate |
| Diuretics (Furosemide) | Increased risk of hypokalemia. | Moderate |
| Phenytoin, Carbamazepine, Rifampicin | May decrease doxofylline levels by inducing metabolism, reducing efficacy. | Moderate |
| Warfarin | Potential increased anticoagulant effect; monitor INR. | Moderate |
Same composition (Doxofylline (400mg)), different brands: