Drug interactions
Guanfacine + Lofexidine
Severity: Major
Guanfacine and Lofexidine: 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
Both drugs are central alpha-2 adrenergic agonists that lower blood pressure and heart rate. Taking them together duplicates therapy and can cause marked hypotension, bradycardia, sedation and syncope.
What this interaction means in plain words
Guanfacine and Lofexidine 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.
Guanfacine belongs to Cardiovascular; Lofexidine belongs to Central Nervous System.
Why it happens
Duplicate central alpha-2 agonism producing additive sympatholytic, hypotensive and bradycardic effects.
What to do
Avoid concurrent use where possible and choose one alpha-2 agonist. If both are required, monitor blood pressure and heart rate closely and reduce doses as needed.
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 Lofexidine
- Adagrasib + Lofexidine Major
- Alfuzosin + Lofexidine Major
- Amiodarone + Lofexidine Major
- Amisulpride + Lofexidine Major
- Anagrelide + Lofexidine Major
- Apomorphine + Lofexidine Major
Other interactions of Guanfacine
- Clonidine + Guanfacine Major
- Aldesleukin + Guanfacine Moderate
- Amiodarone + Guanfacine Moderate
- Amisulpride + Guanfacine Moderate
- Amitriptyline + Guanfacine Moderate
- Amobarbital + Guanfacine Moderate
Frequently asked questions
Can I take Guanfacine with Lofexidine?
MediHelp rates the interaction as major. Guanfacine and Lofexidine 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. Both drugs are central alpha-2 adrenergic agonists that lower blood pressure and heart rate. Taking them together duplicates therapy and can cause marked hypotension, bradycardia, sedation and syncope.
How serious is the interaction between Guanfacine and Lofexidine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid concurrent use where possible and choose one alpha-2 agonist. If both are required, monitor blood pressure and heart rate closely and reduce doses as needed.
What other medicines interact with Lofexidine?
MediHelp also lists interactions of Lofexidine with, for example, Adagrasib, Alfuzosin, Amiodarone. The full list is on the Lofexidine page.
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