Drug interactions
Lofexidine + Phentolamine
Severity: Moderate
Lofexidine and Phentolamine: 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
Both drugs lower blood pressure, and lofexidine also slows heart rate, so combining them may cause marked hypotension, syncope and bradycardia.
What this interaction means in plain words
Lofexidine and Phentolamine 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 belongs to Central Nervous System; Phentolamine belongs to Cardiovascular.
Why it happens
Additive hypotensive effects: alpha-1 blockade plus central alpha-2 agonism.
What to do
Monitor blood pressure and pulse closely and advise slow postural changes. Reduce the dose of one agent if symptomatic hypotension or bradycardia 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 Phentolamine
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 Phentolamine?
MediHelp rates the interaction as moderate. Lofexidine and Phentolamine 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. Both drugs lower blood pressure, and lofexidine also slows heart rate, so combining them may cause marked hypotension, syncope and bradycardia.
How serious is the interaction between Lofexidine and Phentolamine?
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 and pulse closely and advise slow postural changes. Reduce the dose of one agent if symptomatic hypotension or bradycardia occurs.
What other medicines interact with Phentolamine?
MediHelp also lists interactions of Phentolamine with, for example, Alfuzosin, Avanafil, Doxazosin. The full list is on the Phentolamine page.
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