Drug interactions
Smoking + Theophylline
Severity: Moderate
Smoking and Theophylline: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Tobacco smoking markedly accelerates theophylline clearance, so smokers need higher doses to reach therapeutic levels. Stopping smoking can lead to a rise in concentrations and toxicity if the dose is not reduced.
What this interaction means in plain words
Smoking and Theophylline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Polycyclic aromatic hydrocarbons in smoke induce CYP1A2, the main enzyme metabolizing theophylline.
What to do
Dose according to smoking status and measure serum theophylline levels. Reduce the dose and recheck levels when a patient stops smoking, as induction wanes over one to two weeks.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Theophylline
- Riociguat + Theophylline Contraindicated
- Adenosine + Theophylline Major
- Apalutamide + Theophylline Major
- Bupropion + Theophylline Major
- Carvedilol + Theophylline Major
- Cimetidine + Theophylline Major
Frequently asked questions
Can I take Smoking with Theophylline?
MediHelp rates the interaction as moderate. Smoking and Theophylline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Tobacco smoking markedly accelerates theophylline clearance, so smokers need higher doses to reach therapeutic levels. Stopping smoking can lead to a rise in concentrations and toxicity if the dose is not reduced.
How serious is the interaction between Smoking and Theophylline?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Dose according to smoking status and measure serum theophylline levels. Reduce the dose and recheck levels when a patient stops smoking, as induction wanes over one to two weeks.
What other medicines interact with Theophylline?
MediHelp also lists interactions of Theophylline with, for example, Riociguat, Adenosine, Apalutamide. The full list is on the Theophylline page.
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