Synephrine

A stimulant commonly used for weight management and athletic performance.

Also known as: Bitter Orange Extract

other Names
p-Synephrine, Bitter Orange
primary Benefits
Increased metabolic rate, appetite suppression, enhanced energy
common Dose
20-50 mg, 1-3 times daily
best Form
Standardized extract (as p-synephrine)
timing
30 minutes before meals or exercise
safety Rating
Generally safe at recommended doses, but can increase heart rate and blood pressure

Overview

Synephrine is a naturally occurring alkaloid found in the bitter orange fruit (Citrus aurantium). It is structurally similar to ephedrine, but with a better safety profile. Synephrine is often included in weight loss supplements for its ability to increase metabolism and suppress appetite.

Key Benefits

Boosts Metabolism

Synephrine can increase the body's metabolic rate, leading to more calories burned at rest.

Suppresses Appetite

It may help reduce feelings of hunger, making it easier to stick to a calorie-controlled diet.

Enhances Energy and Focus

Synephrine has stimulant properties that can improve energy levels and mental focus.

Dosage & How to Take

Synephrine dosage should be started low to assess tolerance. It is often stacked with other fat-burning ingredients.

PurposeDoseNotes
Weight Management20-30 mg, 1-3 times dailyDo not exceed 100 mg per day.
Athletic Performance50 mgTake 30-60 minutes before exercise.

Best Time to Take

Take 30 minutes before meals to help with appetite control, or before a workout for an energy boost.

With or Without Food

Can be taken with or without food.

Forms & Bioavailability

FormAbsorptionBest ForNotes
Standardized ExtractHighAccurate dosingLook for products standardized for p-synephrine.
CapsulesHighConvenienceEasy to take and dose.

Side Effects & Safety

Common

  • Increased heart rate, elevated blood pressure, jitters

Rare

  • Headaches, anxiety, insomnia

Contraindications

  • Individuals with heart conditions, high blood pressure, or anxiety should avoid synephrine.

Interactions

MAOIs (Monoamine Oxidase Inhibitors)Important

Can lead to a dangerous increase in blood pressure.

Other stimulants (e.g., caffeine)Moderate

Can potentiate the stimulant effects and increase the risk of side effects.

Scientific Research

2012International Journal of Medical Sciences

A review of the human clinical studies involving Citrus aurantium (bitter orange) extract and its primary protoalkaloid p-synephrine

The review concluded that p-synephrine does not have significant cardiovascular effects at common dosages.

2017Food and Chemical Toxicology

Safety of p-synephrine: A review

This review found that p-synephrine is safe for human consumption at typical doses.

Food Sources

Bitter orange fruit

Frequently Asked Questions

Medical Disclaimer

This content is for educational and informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are taking medications. The statements on this page have not been evaluated by the Food and Drug Administration.