Overview
Bitter orange alkaloid used as ephedrine-replacement fat burner.
- Endogenously produced or biosynthesized molecule
- Standardized pharmaceutical- or food-grade supplement
- Combined with cofactors that improve absorption or activity
- Capsule or softgel
- Powder
- Sublingual or buccal
- Liposomal liquid
Mechanism of action
β3-adrenergic agonist; mild thermogenic.
- · β3-adrenergic agonist
- · mild thermogenic
Effects on the body
Organ system effects
P-Synephrine (Bitter Orange) supports mitochondrial ATP production and fatigue resistance.
Evidence-based benefits
Increases resting metabolic rate ~3%
Moderate evidencePotential side effects
- · Jitter
- · Increased HR
- · Arrhythmia
- · Avoid with cardiovascular disease
Drug interactions
Supplement interactions
- A high-quality multivitaminCovers micronutrient cofactors that support most supplement pathways.
- Omega-3 (EPA/DHA)Foundational anti-inflammatory support that complements most regimens.
No specific avoidances listed.
Dosing & bioavailability
Where to buy
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Third-party testedIndependently verified P-Synephrine (Bitter Orange) — look for USP, NSF, or Informed Sport seals on the label for purity and dose accuracy.P-Synephrine (Bitter Orange) third party tested NSF
CapsulesPre-measured P-Synephrine (Bitter Orange) capsules — easiest for travel and consistent daily dosing without scoops or scales.P-Synephrine (Bitter Orange) capsules
PowderBulk unflavored P-Synephrine (Bitter Orange) powder — best cost-per-gram and flexible dosing for stacking or mixing into drinks.P-Synephrine (Bitter Orange) powder unflavored
Best sellersMost-purchased P-Synephrine (Bitter Orange) products on Amazon — a quick way to see what's reviewed widely before you commit.P-Synephrine (Bitter Orange) best sellerScientific evidence8Show studiesHide studies
p-Synephrine on metabolic rate
Stohs SJ, et al.
Crossover study in 50 adults.
50 mg p-synephrine raised resting metabolic rate by 65 kcal.
PubMed: P-Synephrine (Bitter Orange) — Increases resting metabolic rate ~3%
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