What Is PMD (Citrepel®) and How Does It Repel Insects?

TL;DR — key takeaways

• PMD (para-menthane-3,8-diol) is a plant-derived active ingredient that repels mosquitoes and ticks by masking the human scent cues insects use to find you.
• It is the only plant-based repellent recommended by the CDC alongside synthetic actives like DEET, picaridin and IR3535, and it is registered by the US EPA.
• PMD is most commonly produced from lemon eucalyptus, but incognito® makes its own PMD — branded Citrepel® — from Javanese citronella (Cymbopogon winterianus).
• PMD gives DEET-free, long-lasting protection and is a genuine, evidence-backed alternative for people who want to avoid synthetic repellents.
• Typical protection lasts several hours per application; reapply as directed on the product label, especially after swimming or heavy sweating.

If you have ever compared insect repellents, you have probably seen the letters PMD on a label and wondered what they mean. PMD is short for para-menthane-3,8-diol, and it is the plant-based active ingredient at the heart of every incognito® repellent. This guide explains what PMD is, where it comes from, how it actually keeps mosquitoes and ticks away, and how it compares to other repellent ingredients.

What is PMD?

PMD (para-menthane-3,8-diol) is a naturally occurring compound and the active substance in oil of lemon eucalyptus (often abbreviated OLE). It is the ingredient responsible for the repellent effect — the rest of the essential oil provides little lasting protection on its own. Because refined PMD gives far more reliable results than raw plant oil, health authorities draw a clear line between the two: PMD is recommended, while unrefined ‘natural’ oils generally are not.

Crucially, PMD is the only plant-derived repellent active recognised by the US Centers for Disease Control and Prevention (CDC) as effective enough to sit alongside DEET, picaridin and IR3535. That recognition is what separates PMD from the many botanical repellents that smell pleasant but wear off within minutes.

Where does incognito®’s PMD come from?

Here is a distinction worth understanding. PMD is most commonly manufactured from the oil of the lemon eucalyptus tree (Corymbia citriodora). incognito®, however, produces its own PMD — under the brand name Citrepel® — from Javanese citronella (Cymbopogon winterianus) grown for the purpose.

The result is the same well-studied active ingredient, para-menthane-3,8-diol, delivered in a formulation that is DEET-free, vegan and biodegradable. So when you read ‘PMD’ or ‘Citrepel®’ on an incognito® bottle, you are looking at the same class of active that the CDC and ECDC point travellers towards.

How does PMD repel insects?

Mosquitoes and ticks do not see you the way you see them — they track you by smell. A female mosquito locates a host using a combination of carbon dioxide from your breath, body heat, moisture and hundreds of skin-odour molecules such as lactic acid.

PMD works primarily by interfering with that odour-detection system. Two things happen when you apply it:

1. Masking: PMD’s strong scent overlays and confuses the human-scent signals an insect is homing in on, so you become much harder to locate.
2. Deterrence: insects find the compound itself unpleasant and tend to avoid landing on treated skin.

In other words, a repellent like PMD does not kill insects — it makes you difficult to find and unappealing to land on. That is exactly what you want from something you apply to skin.

How does PMD compare to other repellent ingredients?

The main skin-applied actives recognised by the EPA and CDC are DEET, picaridin, IR3535 and PMD. Each works; the differences are in origin, feel and duration.

All four are effective options — the right choice depends on your priorities. If avoiding synthetic chemistry matters to you, PMD is the plant-based active that delivers comparable protection at lower concentrations, which is why it is the one botanical ingredient the health authorities endorse.

How long does PMD protection last?

Duration depends on concentration, activity and conditions. As a general guide, a PMD-based repellent provides several hours of protection per application. Sweat, water and simply rubbing against clothing all shorten that window, so reapplication matters more than the number on the label.

Always follow the reapplication guidance on your specific product, and top up after swimming, towelling off or long periods of heavy sweating.

Is PMD safe?

PMD is registered with the US EPA as a skin-applied repellent active and is recommended for use by the CDC and the European Centre for Disease Prevention and Control (ECDC). As with any repellent, use it as directed: apply to exposed skin, avoid eyes and mouth, and follow the label — including any guidance on use for young children. Product labels carry the definitive age and usage instructions for each formulation, so check yours rather than relying on general rules of thumb.

How incognito® helps

Every incognito® repellent is built around PMD (Citrepel®) rather than DEET. The clinically proven Insect Repellent Spray gives you DEET-free, vegan protection against both mosquitoes and ticks in an easy, non-greasy spray — the plant-based active the CDC endorses, in a formula that is kind to skin and biodegradable. It is the simplest way to put the science of PMD to work whether you are travelling, hiking or just enjoying the garden at dusk.

FAQs

What does PMD stand for?
PMD stands for para-menthane-3,8-diol, a plant-derived active ingredient that repels mosquitoes and ticks.

Is PMD the same as citronella?
Not quite. Citronella oil offers only brief protection, whereas PMD is the refined, longer-lasting active. incognito® produces its PMD (Citrepel®) from Javanese citronella, but the finished active is far more effective than raw citronella oil.

Is PMD the same as DEET?
No. DEET is a synthetic compound, while PMD is plant-derived. Both are recommended by the CDC, but PMD is the only plant-based active on that list and is the DEET-free choice.

Does PMD repel ticks as well as mosquitoes?
Yes. PMD is recommended against both mosquitoes and ticks, which makes it useful for gardens, hikes and travel alike.

How often should I reapply PMD repellent?
Protection lasts several hours per application. Reapply according to your product label, and always top up after swimming or heavy sweating.

Is PMD suitable for children?
Follow the age and usage guidance printed on your specific product label, which gives the definitive instructions for each formulation.

Sources

• CDC — Prevent Mosquito Bites (EPA-registered repellents, including OLE/PMD)
• EPA — Skin-Applied Repellent Ingredients (DEET, OLE/PMD, picaridin, IR3535)
• ECDC — Protective measures against mosquitoes
• NHS — Insect bites and stings

This article is for general information only and is not medical advice. Always read and follow the product label, and consult a healthcare professional about protection that is appropriate for you or your children.