Drug interactions
Lofexidine + Phenoxybenzamine
Severity: Moderate
Lofexidine and Phenoxybenzamine: 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
Lofexidine lowers blood pressure through central sympatholysis, and phenoxybenzamine causes vasodilation through irreversible alpha-adrenergic blockade. Together they can cause marked hypotension, orthostatic symptoms and reflex changes in heart rate.
What this interaction means in plain words
Lofexidine and Phenoxybenzamine 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
Additive hypotensive pharmacodynamic effects from central alpha-2 agonism and peripheral alpha-1 blockade.
What to do
Monitor supine and standing blood pressure and heart rate when starting or adjusting either drug, and counsel patients about orthostatic dizziness. Reduce the dose of one agent if symptomatic hypotension occurs.
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 Lofexidine
- Adagrasib + Lofexidine Major
- Alfuzosin + Lofexidine Major
- Amiodarone + Lofexidine Major
- Amisulpride + Lofexidine Major
- Anagrelide + Lofexidine Major
- Apomorphine + Lofexidine Major
Frequently asked questions
Can I take Lofexidine with Phenoxybenzamine?
MediHelp rates the interaction as moderate. Lofexidine and Phenoxybenzamine 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. Lofexidine lowers blood pressure through central sympatholysis, and phenoxybenzamine causes vasodilation through irreversible alpha-adrenergic blockade. Together they can cause marked hypotension, orthostatic symptoms and reflex changes in heart rate.
How serious is the interaction between Lofexidine and Phenoxybenzamine?
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 supine and standing blood pressure and heart rate when starting or adjusting either drug, and counsel patients about orthostatic dizziness. Reduce the dose of one agent if symptomatic hypotension occurs.
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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