Drug interactions
Apalutamide + Theophylline
Severity: Major
Apalutamide and Theophylline: major 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
Apalutamide is a potent enzyme inducer and can lower theophylline exposure, leading to loss of bronchodilator control. Theophylline has a narrow therapeutic window, so subtherapeutic levels may worsen asthma or COPD.
What this interaction means in plain words
Apalutamide and Theophylline can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Apalutamide belongs to Endocrine; Theophylline belongs to Respiratory.
Why it happens
Apalutamide induces CYP1A2 and CYP3A4, increasing theophylline metabolism.
What to do
Monitor serum theophylline concentrations and clinical response after starting apalutamide, and increase the dose if needed. Consider an alternative bronchodilator if control is inadequate.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Theophylline
- Riociguat + Theophylline Contraindicated
- Adenosine + Theophylline Major
- Bupropion + Theophylline Major
- Carvedilol + Theophylline Major
- Cimetidine + Theophylline Major
- Ciprofloxacin + Theophylline Major
Other interactions of Apalutamide
- Apalutamide + Cabotegravir Contraindicated
- Apalutamide + Cobicistat Contraindicated
- Apalutamide + Doravirine Contraindicated
- Apalutamide + Elbasvir / grazoprevir Contraindicated
- Apalutamide + Ensitrelvir Contraindicated
- Apalutamide + Fostemsavir Contraindicated
Frequently asked questions
Can I take Apalutamide with Theophylline?
MediHelp rates the interaction as major. Apalutamide and Theophylline can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Apalutamide is a potent enzyme inducer and can lower theophylline exposure, leading to loss of bronchodilator control. Theophylline has a narrow therapeutic window, so subtherapeutic levels may worsen asthma or COPD.
How serious is the interaction between Apalutamide and Theophylline?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor serum theophylline concentrations and clinical response after starting apalutamide, and increase the dose if needed. Consider an alternative bronchodilator if control is inadequate.
What other medicines interact with Theophylline?
MediHelp also lists interactions of Theophylline with, for example, Riociguat, Adenosine, Bupropion. The full list is on the Theophylline page.
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