Indications

Filodox (Doxophylline) is a bronchodilator used to treat the following conditions:

• Bronchial asthma
• Bronchospasm
• Chronic obstructive pulmonary disease (COPD)
• Pulmonary disease with a spastic bronchial component

Pharmacology

Doxophylline is a bronchodilator that works by selectively inhibiting the enzyme phosphodiesterase 4, which leads to the relaxation of bronchial smooth muscle. Unlike Theophylline, it has a lower affinity for adenosine A1 and A2 receptors, which may contribute to its better safety profile. Doxophylline is also reported to inhibit platelet-activating factor (PAF) and the production of leukotrienes.

Dosage & Administration

• Adults: 400 mg tablet two or three times daily.
• Elderly: 200 mg tablet two or three times daily.
• Children (>12 years): 10 ml syrup or 200 mg tablet two or three times daily.
• Children (6-12 years): 6-9 mg/kg body weight twice daily (e.g., 3 ml for a 10 kg child).
• A once-daily 400 mg SR tablet can be taken if prescribed.

Interaction

Do not use Filodox with other xanthine preparations. Limit caffeine consumption. Use with caution when taken with ephedrine or other sympathomimetic drugs. Several drugs (e.g., erythromycin, cimetidine, propanolol) and factors like age and certain diseases can decrease the drug's clearance, potentially increasing its plasma levels. In contrast, phenytoin and cigarette smoking can increase its clearance, possibly requiring a dosage increase.

Contraindications

Filodox is contraindicated in individuals with a known hypersensitivity to the drug or other xanthine derivatives. It is also contraindicated in patients with acute myocardial infarction, hypotension, and during lactation.

Side Effects

Common side effects include nausea, vomiting, epigastric pain, headache, irritability, insomnia, and tachycardia. In rare cases, hyperglycemia or albuminuria may occur. Overdose can lead to severe cardiac arrhythmias and tonic-clonic seizures.

Pregnancy & Lactation

While animal studies have not shown adverse effects on pre- and postnatal growth, the use of Filodox during pregnancy should be carefully evaluated based on the risk-benefit ratio due to limited human data. The drug is contraindicated during lactation.

Precautions & Warnings

Caution should be used when administering Filodox to patients with cardiac disease, hypertension, severe hypoxemia, hyperthyroidism, or liver/kidney impairment. The drug's clearance can be slower in these patients, and dosage adjustment may be necessary. Monitoring of blood levels is recommended in these cases.

Overdose Effects

Overdose may cause severe cardiac arrhythmias and seizures. If this occurs, treatment should be discontinued. Since there is no specific antidote, symptomatic treatment for cardiovascular collapse should be initiated.

Therapeutic Class

Filodox is classified as a Bronchodilator and a Methyl xanthine derivative.

Storage Conditions

Store in a dry place, away from light and heat. Keep out of the reach of children.