Drug interactions
Chloramphenicol + Guanfacine
Severity: Moderate
Chloramphenicol and Guanfacine: 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
Guanfacine is cleared mainly by CYP3A4, so inhibitors increase its exposure. This can cause excessive hypotension, bradycardia and sedation.
What this interaction means in plain words
Chloramphenicol and Guanfacine 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.
Chloramphenicol belongs to Anti Bacterial; Guanfacine belongs to Cardiovascular.
Why it happens
Chloramphenicol inhibits CYP3A4, reducing the metabolism of guanfacine.
What to do
Monitor blood pressure, heart rate and sedation, and consider reducing the guanfacine dose during coadministration. Increase the dose again if needed after the antibiotic is stopped.
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 Chloramphenicol
Other interactions of Guanfacine
- Clonidine + Guanfacine Major
- Guanfacine + Lofexidine Major
- Aldesleukin + Guanfacine Moderate
- Amiodarone + Guanfacine Moderate
- Amisulpride + Guanfacine Moderate
- Amitriptyline + Guanfacine Moderate
Frequently asked questions
Can I take Chloramphenicol with Guanfacine?
MediHelp rates the interaction as moderate. Chloramphenicol and Guanfacine 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. Guanfacine is cleared mainly by CYP3A4, so inhibitors increase its exposure. This can cause excessive hypotension, bradycardia and sedation.
How serious is the interaction between Chloramphenicol and Guanfacine?
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 blood pressure, heart rate and sedation, and consider reducing the guanfacine dose during coadministration. Increase the dose again if needed after the antibiotic is stopped.
What other medicines interact with Chloramphenicol?
MediHelp also lists interactions of Chloramphenicol with, for example, Adagrasib, Avapritinib, Bcg vaccine live. The full list is on the Chloramphenicol page.
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