Drug interactions
Nelfinavir + Theophylline
Severity: Moderate
Nelfinavir 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
Nelfinavir inhibits CYP3A4, a minor theophylline pathway, but it may also induce other enzymes, so the net effect is unpredictable. Theophylline levels could change in either direction.
What this interaction means in plain words
Nelfinavir 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.
Nelfinavir belongs to Anti Virals; Theophylline belongs to Respiratory.
Why it happens
Nelfinavir inhibits CYP3A4 and may alter other metabolic pathways, with an unpredictable net effect on theophylline clearance.
What to do
Monitor serum theophylline concentrations when starting or stopping nelfinavir and adjust the dose accordingly.
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
Other interactions of Nelfinavir
- Alfuzosin + Nelfinavir Contraindicated
- Avanafil + Nelfinavir Contraindicated
- Dronedarone + Nelfinavir Contraindicated
- Eletriptan + Nelfinavir Contraindicated
- Ergotamine + Nelfinavir Contraindicated
- Flibanserin + Nelfinavir Contraindicated
Frequently asked questions
Can I take Nelfinavir with Theophylline?
MediHelp rates the interaction as moderate. Nelfinavir 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. Nelfinavir inhibits CYP3A4, a minor theophylline pathway, but it may also induce other enzymes, so the net effect is unpredictable. Theophylline levels could change in either direction.
How serious is the interaction between Nelfinavir 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: Monitor serum theophylline concentrations when starting or stopping nelfinavir and adjust the dose accordingly.
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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