Theophylline 250mg

Prolonged release tablet

Nuelin SA are indicated for the prophylaxis and treatment of reversible bronchospasm associated with asthma and chronic obstructive pulmonary disease. Because effective plasma levels are maintained for up to twelve hours from a single dose, less frequent dosing is required than with conventional theophylline preparations.

ADULTS: One tablet twice daily, preferably after food, increasing to two tablets twice daily, if necessary.

Nuelin SA-250 are not recommended for children under six years.

Nuelin SA-250 tablets are scored and may be halved but should not be crushed or chewed.

The dosage should be titrated for each individual and adjusted with caution. Serum theophylline levels should be monitored to ensure that they remain within the therapeutic range.

 6 TO 12 YEARS: One tablet twice daily, preferably after food.

Elderly patients may require lower doses due to reduced theophylline clearance.

Porphyria

Hypersensitivity to any constituent or to xanthines.

Concomitant use with ephedrine in children.

The patients response to therapy should be carefully monitored. Worsening of asthma symptoms requires urgent medical attention.

Use with caution in patients with cardiac arrhythmias, peptic ulcer, hyperthyroidism, severe hypertension, acute porphyria, hepatic dysfunction, chronic alcoholism, acute febrile illness and chronic lung disease.

Smoking and alcohol consumption may increase theophylline clearance and increased doses of theophylline are therefore required. In patients with cardiac failure, hepatic dysfunction/disease and fever the reverse is true and these patients may require a reduced dosage.

Alternative bronchodilator therapy should be used in patients with a history of seizures.

It is not recommended that the product be used concurrently with other preparations containing xanthine derivatives.

WARNINGS: Xanthines can potentiate hypokalaemia resulting from beta-2-agonist therapy steroids, diuretics and hypoxia. Particular caution is advised in severe asthma. It is recommended that serum potassium levels are monitored in such situations.

PRECAUTIONS: In the case of an acute asthmatic attack in a patient receiving a sustained action theophylline preparation, great caution should be taken when administering intravenous aminophylline. Half the recommended loading dose of aminophylline (generally 6 mg/kg) should be given, i.e. 3 mg/kg, cautiously.

Cimetidine, allopurinol, corticosteroids, frusemide, isoprenaline, oral contraceptives, thiobendazole, ciprofloxacin, erythromycin or other macrolide antibiotics and the calcium channel blockers, diltiazem and verapamil, nizatidine, norfloxacin, isoniazid, fluconazole, carbimazole, mexiletine, propafenone, oxpentifylline, disulfiram, viloxazine, interferon alfa, and influenza vaccine increase plasma theophylline concentrations. A reduction of the theophylline dosage is recommended.

Phenytoin, carbamazepine, barbiturates, rifampicin, sulphinpyrazone, ritonavir, primidone and aminoglutethimide may reduce plasma theophylline concentrations and therefore the theophylline dosage may need to be increased.

Theophylline can increase lithium excretion.

The concomitant use of theophylline and fluvoxamine should usually be avoided. Where this is not possible, patients should have their theophylline dose halved and plasma theophylline should be monitored closely.

Plasma concentrations of theophylline can be reduced by concomitant use of the herbal remedy St John's wort (Hypericum perforatum).

Other interactions:

β-Blockers: antagonism of bronchodilation.

Ketamine: reduced convulsive threshold.

Doxapram: increased CNS stimulation.

Also see Warnings.

The side-effects commonly associated with xanthine derivatives such as nausea, gastric irritation, palpitations, tachycardia, arrhythmias, convulsions, headache, CNS stimulation and insomnia are much diminished when a sustained action preparation such as Nuelin SA is used. These side-effects are mild and infrequent when the plasma concentration is maintained at less than 20 microgrammes/ml.

Meda Pharmaceuticals

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