The science
Not just Manuka — the science behind medical grade honey.
Manuka leads the category, but it doesn't own it. Peroxide-driven honeys, polyphenol-rich Honeydew, Ulmo, Heather, Buckwheat and Tualang each carry their own chemistry — and their own clinical case for medical grade use.
Activity chemistry
MGO, DHA, peroxide — and the osmotic backbone every honey shares.
Most honeys derive their antimicrobial activity from hydrogen peroxide, generated when the bee enzyme glucose oxidase encounters glucose in the wound bed. Peroxide activity is real — but fragile. It collapses under heat, light, dilution, and tissue catalase.
Manuka's signature is methylglyoxal (MGO), formed by the slow, non-enzymatic conversion of dihydroxyacetone (DHA) from the nectar of Leptospermum scoparium. MGO is stable, dose-dependent, and survives gamma irradiation.
But the chemistry every medical-grade honey shares — Manuka or not — is osmosis. Honey's high sugar concentration and low water activity draw fluid out of the wound bed, lifting slough and necrotic tissue (autolytic debridement) while sustaining the moist wound-healing environment modern wound care depends on. Low pH adds a further antibacterial layer.
Manuka is not always the right answer. It is by far the most expensive honey in the category — the price difference between a standard peroxide-active honey and high-MGO Manuka can be more than 10×. For many indications — burns first-aid, simple abrasions, autolytic debridement, OTC and consumer wound formats — a well-specified peroxide-active or polyphenol-rich honey can deliver the osmotic, debriding and moist-healing benefits at a fraction of the cost. The right choice is indication-led and budget-led, not brand-led.
Activity comparison
| Property | Peroxide | Manuka |
|---|---|---|
| Heat stable | — | ✓ |
| Catalase resistant | — | ✓ |
| Dose quantifiable | variable | mg/kg MGO |
| Survives gamma | partial | ✓ |
| Osmotic / debriding | ✓ | ✓ |
| Moist wound healing | ✓ | ✓ |
| Relative cost | baseline | up to 10×+ |
Osmosis, debridement and moist wound healing are shared honey properties — not Manuka-exclusive. Indication and budget should drive the honey choice.
Rheology & crystallisation
Thixotropic by nature.
Manuka is naturally thixotropic — it behaves as a gel at rest and flows under shear. No carbomers, no gelling agents, no excipients you'll have to defend in your dossier. Jelly-bush (Australia) and Heather (Scotland) share this rheology at a fraction of the cost when MGO isn't required.
The crystallisation challenge.
100% Manuka crystallises. It is a natural process driven by a higher glucose-to-fructose ratio than honeys like Acacia. For a medical device this is a stability and dosing question, not a quality failure — and one that has elegant formulation solutions.
Beyond Manuka
The other medical-grade candidates.
Manuka's MGO chemistry made it the category leader, but it isn't the only honey with a credible mechanism of action. Each of these has peer-reviewed evidence behind it — and a place in the conversation.
Ulmo (Chile)
Eucryphia cordifolia
Peroxide + polyphenols
Comparative trials show greater efficacy than Manuka against certain MRSA strains in vitro. Strong wound-care candidate in South America.
Heather (UK / Europe)
Calluna vulgaris
Peroxide + thixotropic rheology
Naturally gel-like — rare outside Manuka. Used in Scottish and Scandinavian wound applications; no MGO but strong osmotic and peroxide activity.
Honeydew (Europe)
Forest secretions, not nectar
Polyphenols + oligosaccharides
Higher mineral and antioxidant load than nectar honeys. 2024 data suggest stronger antiviral activity than Manuka in specific models.
Buckwheat (N. America / E. Europe)
Fagopyrum esculentum
Polyphenols + peroxide
Highest phenolic content of common honeys. Cochrane-grade evidence as a paediatric cough antitussive (vs placebo and dextromethorphan).
Tualang (Malaysia)
Koompassia excelsa
Phenolics + flavonoids
Studied in burns, oral mucositis and diabetic wounds. Comparable antibacterial profile to Manuka against several Gram-negative pathogens.
Jelly-bush (Australia)
Leptospermum polygalifolium
MGO (same family as Manuka)
Australian Leptospermum cousin — frequently equal or higher MGO than NZ Manuka. The basis of Medihoney's original supply.
Sidr (Yemen / Middle East)
Ziziphus spina-christi
Peroxide + traditional use
Long ethnomedical history; emerging lab data on antibacterial and antifungal activity. Premium-priced and supply-constrained.
Acacia & clover (global)
Robinia, Trifolium spp.
Peroxide-active
Mild peroxide activity; valuable as a base or supplemented honey (see L-Mesitran). Crystallise slowly — useful in stable formulations.
Activity drivers vary: peroxide (glucose-oxidase generated, fragile but ubiquitous), methylglyoxal (Manuka and Jelly-bush, stable and quantifiable), bee defensin-1 (a peptide present at variable levels across honeys, central to Revamil), polyphenols and flavonoids (Honeydew, Buckwheat, Tualang) and osmolarity (every honey, by virtue of being honey). A medical-grade specification picks one or more of these and engineers them to survive sterilisation and shelf life.
Sterilisation
Why medical honey is gamma irradiated.
Honey is dense, viscous and water-active in ways that defeat conventional terminal sterilisation. Heat denatures peroxide activity and degrades fragile bioactives; steam can't penetrate a sealed honey matrix evenly. That is why the majority of medical honey-based products are terminally sterilised by gamma irradiation as a finished good.
Industry standard
Gamma (Co-60)
Deep, uniform penetration through dense honey and primary packaging. Validated to ISO 11137. Preserves MGO; modest, predictable effect on peroxide activity. The default for almost every medical-grade Manuka product on the market.
Alternative
E-beam
Faster dose delivery and tighter dose distribution than gamma, but limited penetration depth — suitable for thin dressings, tulles and low-density formats rather than bulk honey tubes or jars.
Alternative
EtO (ethylene oxide)
A surface sterilant — gas does not penetrate a sealed honey matrix, and residuals are tightly regulated under ISO 10993-7. Used for combination devices and dressing carriers, rarely for the honey itself.
Related reading
Continue reading
Definition
What is Medical Grade Honey?
The five conditions a honey must satisfy, the regulatory gap, and the working specification we hold suppliers to.
Applications
Clinical use cases & evidence
Wound care, ophthalmology, antimicrobial stewardship and emerging frontiers — with trial identifiers.
Testing
The analytical panel
Botanical identity, MGO + DHA, leptosperin, residues and moisture — the tests behind a Medical Grade specification.
For patients
Medical honey patient guide
A plain-English walkthrough for patients and carers — how it works, what the dressing feels like, side effects.
Bibliography
101 key studies, grouped
The PubMed evidence cluster behind the 2025 refined Medical-Grade Honey definition — mechanisms, ulcers, burns, surgical, paediatric, veterinary.