Synephrine (Bitter Orange)
Overview
Synephrine (p-synephrine, C9H13NO2, CID 7172) is a protoalkaloid beta-3 adrenergic agonist from unripe Citrus aurantium (bitter orange) fruit, structurally related to ephedrine. Meta-analysis of 18 clinical trials shows no significant weight loss despite measurable sympathomimetic effects: systolic BP increases ~6 mmHg, diastolic ~4 mmHg, elevated resting heart rate with prolonged use. CRITICAL INTERACTIONS: absolutely contraindicated with MAO inhibitors (risk of hypertensive crisis); significant additive cardiovascular effects with caffeine, ephedrine, and other stimulants; potentiates decongestants and some antidepressants. FDA surveillance documented cardiovascular adverse events (arrhythmia, MI, stroke), particularly in hypertensive patients or those with cardiac history. CAUTION: not recommended for routine use given poor efficacy/risk profile.
Dosage
20 mg · Morning · Take with food
Key Interactions
1 verified interaction found
Caffeine and synephrine (bitter orange) are both sympathomimetics. Their combination produces additive cardiovascular effects: increased heart rate, blood pressure, and risk of arrhythmia. Multiple adverse event reports exist, including deaths in the context of high-dose weight-loss supplements.
Avoid combination, especially at high doses. Contraindicated in cardiovascular disease, hypertension, or arrhythmia.
View details →Scientific Sources
Frequently Asked Questions
What is Synephrine (Bitter Orange) used for?
Synephrine (p-synephrine, C9H13NO2, CID 7172) is a protoalkaloid beta-3 adrenergic agonist from unripe Citrus aurantium (bitter orange) fruit, structurally related to ephedrine.
What is the recommended dosage for Synephrine (Bitter Orange)?
20 mg. Morning. Take with food.
Does Synephrine (Bitter Orange) interact with other supplements?
Synephrine (Bitter Orange) has 1 verified interactions. Top: Caffeine.
When is the best time to take Synephrine (Bitter Orange)?
Morning. Take with food.
Is Synephrine (Bitter Orange) safe to combine with other supplements?
Always check interactions before combining supplements. Use VitalStack to verify your full stack for free.
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