Suppliers will quote you 6%, 30%, 60%, 95%, 98% synephrine and leave you to figure out the rest. Most buyers just pick whatever fits the budget. Then the product underperforms and everyone blames the ingredient.
The ingredient is usually not the problem.
Six percent is a whole-plant extract. The synephrine is there but so is everything else — flavonoids, volatile oils, the full bitter orange matrix. If your label says "bitter orange fruit extract" and you want that to mean something, this is where you start. It is also where quality variance is highest because you are working with a complex extract, not a concentrated single compound.
Thirty percent is the most common spec for sports nutrition and weight management capsules. Enough concentration to hit 50–100 mg of p-synephrine per day in a normal serving size without needing a massive fill weight. Most pre-workout and fat burner formulas land here.
Ninety-five and 98% are essentially isolated p-synephrine. The natural matrix is largely gone. These grades make sense for pharmaceutical applications or very precise dosing requirements. For standard dietary supplements, the extra cost rarely justifies itself.
The mistake people make with 6% material is assuming cheaper automatically means worse. Sometimes it does. A poorly sourced 6% extract with inconsistent raw material quality will give you batch-to-batch synephrine variance that makes your finished product unreliable. That is a supplier problem, not a spec problem. Always ask for batch-specific HPLC data, not just a blanket spec sheet.
P-synephrine gets lumped in with ephedrine because they look similar on paper. The FDA banned ephedra in 2004, supplement brands rushed to use citrus aurantium as a replacement, stacked it with caffeine and called it safe. Some of those products caused problems.
But when you look at p-synephrine on its own, the picture is different. Around 30 human studies at normal doses found no significant effects on heart rate or blood pressure. A 60-day placebo-controlled trial at up to 98 mg daily reported no adverse effects. The case reports that circulated were almost all multi-ingredient products — caffeine, yohimbine, other stimulants mixed in — not bitter orange synephrine alone.
The real issue in the market is adulteration. Methylsynephrine and isopropyloctopamine are synthetic stimulants that have been found in commercial bitter orange supplement products. They are not natural compounds in Citrus aurantium. They bind more aggressively to adrenergic receptors than p-synephrine does and that is where the cardiovascular risk actually comes from.
So the safety question is not really about the plant. It is about whether what is in the bag matches what is on the label. Third-party testing for synthetic adulterants should be standard. If a supplier cannot produce it, move on.
If your product targets competitive athletes, synephrine is on the NCAA banned list. Not on the WADA prohibited list as of 2025, but WADA is monitoring it. More importantly, octopamine — a related compound naturally present in some citrus aurantium extracts — is on the WADA prohibited list. Your COA needs to address octopamine content if you are selling into that market. A lot of brands miss this.
On dosing: Health Canada puts 1–50 mg p-synephrine per day as unlikely to cause adverse effects in healthy adults. Most human research uses 50–100 mg daily. At 6% extract, 50 mg of p-synephrine needs about 830 mg of extract per serving. At 30%, you need around 167 mg. That difference matters a lot for capsule fill weight and formulation cost.
One more thing — citrus aurantium supplement products are fully legal in the US, EU, and most major markets. The controversy around this ingredient has always been about how it gets used in products, not about the plant itself.
For most dietary supplement applications 6–30% is the practical range. Higher concentrations are rarely necessary and significantly more expensive.
Yes. The flavonoid fraction supports antioxidant and anti-inflammatory activity. Whole-plant extracts at lower synephrine percentages retain more of this.
Ask for HPLC testing that identifies p-synephrine specifically and screens for methylsynephrine and isopropyloctopamine. Any serious supplier has this.
We supply citrus aurantium extract synephrine across multiple standardizations with complete COA documentation and clearly defined product specifications. Sample requests and quotes are available directly from our sales team.
