The three routes in — aromatic, topical, internal — with the drop counts, the dilutions and the judgement that go with each.
~11 min read
There are only three ways a compound made by a plant gets from a bottle into a person: the air you breathe, the surface of your skin, the digestive tract. Aromatic, topical, internal. Almost every mistake comes from choosing the wrong one.
Those three letters are the vocabulary of this app. Every oil in the library carries them as its methods, and the DIY collection files preparations under them.
A — Aromatic
Molecules leave the liquid into the air and you breathe them. The fastest route, and the one with fewest rules — nothing lands on skin and nothing is swallowed.
T — Topical
A drop, in a carrier oil, on skin. Slower, and far more controllable: you decide where it goes and how strong. The whole method turns on dilution.
I — Internal
Into food, into a drink, into a vegetable capsule — and only if the label on your own bottle says the oil is for internal use. It delivers by far the largest share, which is why the amount is a single drop.
Why each route works at all is the oil effect. This is the other half: what to do, in drops and minutes. Which doTERRA products you can buy differs by country, and so does what their labels permit; the method stands where the bottle changes.
Start here if you are new. Nothing is on skin, nothing is swallowed, and the dose is set by the size of the room rather than anything you measure.
An ultrasonic diffuser holds 100 to 150 millilitres and breaks water into cool mist with a vibrating ceramic disc. Fill to the line, then add the oil to the water rather than the other way round. Three to four drops of a single oil, or four to six of a blend, suits an ordinary room.
Run it thirty to sixty minutes, on the intermittent setting if it has one. Olfactory receptors report change rather than steady state, so a continuous aroma stops being perceived within minutes while the room carries on filling; an intermittent run gives a stronger impression from less material, which the nervous system explains. Stand it a metre or two from where people sit, never in a closed room an infant or animal cannot leave.
A diffuser is not an extractor, and it does not clean air
It adds molecules to a room and removes nothing. It will not pull cooking smoke from a kitchen, will not filter dust, and does not sanitise — that is what an extractor fan, an open window and a filter are for. Diffuse into air already clear.
From your palms
One or two drops into a cupped palm, cupped an inch from your nose, three to five slow breaths. Never a hot oil, and wash your hands: peppermint at 30–50% menthol on an eyelid is a mistake made once.
A personal inhaler
Ten to fifteen drops onto the cotton wick, cap on, held under one nostril. It reaches you and nobody else — the only aromatic method for a shared room. A wick lasts two months.
Steam from a bowl
One or two drops on a bowl of hot water, not boiling, towel over the head, two to five minutes. The most concentrated aromatic method there is: one drop is enough, two the ceiling. Keep children away — the hazard is the water.
A passive diffuser for a room
Two drops on a cotton pad at the back of a shelf, or on a tissue inside a pillowcase — never the pillow, since oil on bedding is a topical application nobody intended. A reed diffuser takes 60 to 80 drops in 100 millilitres of carrier oil and runs for months.
Diagram to come
A horizontal scale showing how far each aromatic method reaches, drawn as five concentric or stepped zones from smallest to largest, each with its method, its drop count and its duration. Smallest: a personal inhaler tube held under one nostril, a single head in the zone. Next: cupped palms at a face, one head. Next: a steam bowl with a towel, one head, drawn with a small warning marker on the water rather than on the oil. Next: a diffuser on a side table with a mist plume, two or three seated figures in the zone. Largest: a whole room in plan view with a passive diffuser on a shelf and a window ajar, the open window drawn as part of the method rather than an afterthought. Along the bottom, a separate strip labelled as what a diffuser does not do, showing an extractor fan pulling smoke OUT of a kitchen beside a diffuser putting mist IN, with arrows in opposite directions. No condition, symptom or outcome anywhere in the drawing.
Two things accumulate in a reservoir and both of them degrade what comes out of it. The first is oil residue. Monoterpenes oxidise on contact with air, and the thin film left behind after the water has gone turns sticky and then resinous over weeks. It coats the ceramic disc, which works by vibrating fast enough to throw water off its surface; a coated disc throws less, so the mist thins and eventually stops. The second is what grows in standing water left warm in a dark plastic cup for three days, which is the same thing that grows in any standing water and does not become acceptable because there is lavender in it.
There is a smell test for whether you have been doing this. Run plain water with no oil in it for a minute and stand close. A clean diffuser smells of nothing. A neglected one smells faintly of every blend you have run through it for the past two months, in the wrong order, which is what you have actually been putting in the room each evening.
Almost everyone meets topical use as two instructions: put it on, and dilute it first — the second treated as a caution attached to the first. That is the wrong way round. Dilution is the method.
A carrier oil is a fixed oil — fractionated coconut, jojoba, sweet almond — that does not evaporate. It holds volatile constituents against the skin for hours instead of letting them leave as vapour; it spreads two drops over a palm-sized area rather than a coin-sized one, so concentration falls while contact area and time rise; and it keeps skin from meeting a constituent at full strength, which is how sensitisation is avoided. Work to this table.
| Strength | Where it belongs | Per 10 mL | Per 30 mL |
|---|---|---|---|
| 0.5–1% | The face. Children over two. Sensitive or elderly skin. | 1–2 drops | 3–6 drops |
| 1–2% | Daily use over a larger area of an adult — back, legs, a full massage. | 2–4 drops | 6–12 drops |
| 2–3% | A small localised area on an adult, for a short run of days rather than indefinitely. | 4–6 drops | 12–18 drops |
| 0.5% or less | Hot oils at any age — oregano, thyme, cinnamon bark, cassia, clove. | 1 drop | 3 drops |
For children under two, ask a healthcare practitioner before any topical use. Keep peppermint, eucalyptus and rosemary off the face and neck of a child under six. And the expressed citrus oils — lemon, lime, grapefruit, bergamot, wild orange — carry a rule that has nothing to do with dose: after applying them to skin, keep that skin out of direct sunlight and UV for up to twelve hours. The compounds responsible are furanocoumarins carried across in cold pressing, not the limonene that is 60–75% of lemon oil — which is why distilled citrus oils do not carry it.
Diagram to come
A simple full-body figure, front and back shown side by side, with five application sites marked by a small filled dot and a leader line to a label, and three never-here zones marked differently — an outline ring rather than a filled dot — so the two kinds of marking cannot be confused at a glance. Marked sites: the inside of both wrists and the sides of the neck as one group; behind the ears; the soles of both feet, drawn as a separate small inset of a sole so the whole sole is visible; a general area of interest shown on a forearm and a calf; and a run down either side of the spine on the back view. Never-here: the eyes, the inner ear canal, and a small patch of drawn broken skin on a shin. In the corner, a separate small panel showing the patch test — a coin-sized circle inside a forearm with 24 h and 48 h beside it. No condition, symptom or outcome anywhere in the drawing.
Pulse points — wrists, the sides of the neck, the inner elbows, the temples
Thin skin with vessels close beneath, and the aroma rises to you all day — half topical, half aromatic, which is why it is the classic place for a roller. The temples want care: 1%, well back towards the hairline, never where a finger might carry it to an eye.
The soles of the feet
Thick skin, no hair follicles, very few reactions, and easy to cover with a sock. The site for anything strong, for anything on a child over two, and for hot oils, which belong nowhere else.
The area you actually mean
A shoulder, a calf, a forearm — at the strength in the table, over the whole area rather than one spot, worked in until the skin is no longer wet. Warmth from the massage raises what crosses, which is why the massage is part of the method.
Behind the ears
One drop of a 1% dilution on the bone behind each ear: thin skin, noticed all day, out of the way of anything you touch. Never in the canal, never on the soft inner folds.
The spine
A run down either side, neck to the small of the back — the largest single application there is. Six to twelve drops in 30 millilitres is 1–2%, and it wants somebody else’s hands.
Patch test anything new at its final strength: a coin-sized amount inside a forearm, unwashed, checked at twenty-four hours and again at forty-eight, since sensitisation often shows on the second day. Redness, heat, itching or raised bumps means that oil at that strength is not for you — wash it off with carrier oil first, then soap and water, never water alone. Test each new oil, blend and dilution separately, and always before anything goes on a child. The integumentary system has the barrier in full.
What makes the route possible at all is that these are unusually small molecules — most essential oil constituents sit between about 130 and 220 daltons, far below the rough five-hundred ceiling above which almost nothing crosses intact skin, and small enough to pass a cell membrane where larger molecules cannot. That is a fact about the fraction rather than about any particular oil. What you control is not whether they can cross but how much of them is there, and that is the carrier’s job.
One formula covers every dilution you will ever make. Drops = millilitres × 20 × percentage ÷ 100. The 20 is drops per millilitre from a standard orifice reducer, since a drop is about 0.05 millilitres. So a 10 mL roller at 3% is six drops. A 30 mL bottle at 2% is twelve. A 100 gram jar of body butter at 1% is twenty — for a solid, treat a gram as a millilitre and the sum still works.
A drop is not a precise unit. Thin citrus oils drop smaller than 0.05 mL; thick myrrh, vetiver and sandalwood drop larger, sometimes half as large again. Every count in this app assumes twenty to the millilitre, which is close enough at these strengths — the difference between 2.0% and 2.3% is not a difference that matters. A 15 mL bottle holds roughly 250 drops on that arithmetic, which is worth knowing when a recipe asks for sixty.
You will also meet an older rule of thumb, stated as a drop ratio rather than a percentage: one drop of essential oil to four drops of carrier. It has been printed in a great many places, including on earlier versions of this page. Do the sum on it — one part in five is twenty per cent, which is roughly ten times the daily figure in the table above and forty times what belongs on a child. Any ratio expressed as drops-to-drops rather than drops-to-volume will run high like this, because it quietly assumes a very small total. Work in percentages of a stated volume and the problem disappears.
One practical consequence. Heat, damp skin and anything laid over the top — a plaster, tight clothing, a thick balm — all raise how much of a dilution actually crosses, sometimes several times over. Applying something straight out of a hot bath and then pulling on leggings is a higher effective dose than the percentage on the bottle suggests. Drop a step in the table when two of those three are true.
The label on the bottle in your hand decides, and nothing else does
Everything here is conditional on one thing: the label on your own bottle saying the oil is for internal use. Not the same oil in a photograph, not a recipe written in another country, not a friend’s bottle from a different market. Countries classify concentrated botanicals differently — one treats a flavouring within stated limits as a food ingredient, another as a supplement, another allows no food pathway at all. Same still; the label differs because the law differs. If your bottle does not say it, this section is not for you, and the recipe is still worth making with the herb or the zest.
Where a label does permit it, the direction printed on the bottle is one drop diluted in about 120 millilitres of liquid — four fluid ounces. The amounts here are the smallest of the three.
A drop in a glass of water
One drop in about 120 millilitres, in glass or stainless steel — not plastic. Limonene is 60–75% of lemon oil and a solvent for non-polar materials, so it softens plastics and pulls compounds from the wall into what you are drinking. Oil will not dissolve in water either, so it floats and the first mouthful carries most of it: put the drop into a teaspoon of honey and pour the water over. Honey holds droplets apart where water cannot — four to six drops through 250 grams of it, by the spoon, is more controllable than a drop.
A vegetable capsule
An empty size 00 capsule holds roughly 0.9 millilitres. One drop of essential oil, topped up with fractionated coconut oil, swallowed at once with a glass of water. Do not fill them in advance — the oil softens the shell and a stored capsule leaks.
Under the tongue
The most direct of the internal methods and the most easily overdone. Where a label describes it, take it with something rather than neat — a drop stirred into honey or fractionated coconut oil. Nothing goes on the tongue straight from a bottle, under any label.
In cooking
Into the fat, never the acid; off the heat at the end of anything simmered. For four people, one to two drops of lemon or grapefruit, one to three of wild orange, one of lime or ginger — and a toothpick tip only, never a drop, for peppermint, oregano, thyme, cinnamon bark and clove. Nothing comes back out of a bowl. Cooking with oils is the whole method.
Photograph to come
An overhead shot of a clean worktop holding exactly what an internal preparation is physically made of: a plain glass tumbler of water, a stainless steel bottle, a small dish of runny honey with a teaspoon in it, an open empty vegetable capsule beside a small bottle of fractionated coconut oil, and a single wooden toothpick. One essential oil bottle, label turned away so no product or claim is readable. A plastic sports bottle sits pushed to the far edge of the frame, clearly outside the group. Natural light, no hands, no styling props, no food beyond the honey.
A drop of essential oil does not look like much, and the whole difficulty of the internal route is that it is much more than it looks. The comparison doTERRA gives for peppermint is the clearest one available: one drop of peppermint oil is roughly equivalent to twenty-eight cups of peppermint tea. That is not a figure about strength of flavour. It is about how much plant material had to go into the still for that drop to exist.
The arithmetic underneath it is simple enough to carry. A drop is about 0.05 millilitres, so a 15 millilitre bottle holds around 250 of them. That bottle is the volatile fraction distilled out of many times its own weight in leaf, and the fraction is concentrated precisely because almost everything else in the plant — the water, the fibre, the sugars, the pigments, the bulk that fills a teacup — was left behind in the still. What arrives in the bottle is the part that was present in the leaf at a few per cent and is now present at a hundred.
One habit follows, and it is worth more than any list. When you are unsure between two amounts, use the smaller one. You can always add a second drop tomorrow, and there is no version of this in which you take one back.
Two things are never done, under any label. Nothing neat on the tongue or straight from the bottle, and nothing internal for a child — the same drop is several times the amount relative to body size. Your own bottle’s label decides whether any of this applies.
The route chooses itself once you say plainly what you are trying to do.
What are you actually trying to do?
Five situations, and the route each one points at. Nothing here is about what an oil does — only about which door makes sense for what you want.
Six things shift the figures above, and every one shifts them downward. Safety holds it all at length.
Age, at both ends
Thinner skin with a proportionally larger surface area means the same drop is a larger dose. Under two, ask a healthcare practitioner before any topical use. Over two, work at 0.5–1% on the soles of the feet. Keep peppermint, eucalyptus and rosemary off the face and neck under six. Older and sensitive skin sits in the same band.
Pregnancy and nursing
A conversation with your healthcare practitioner before you use anything, by any route — not a list of permitted oils. The answer is specific to both people involved.
Medication, or being under medical care
Speak to your healthcare practitioner first, and mention the internal route specifically. A swallowed drop passes through the liver before the rest of the body sees any of it, and that is the organ handling most medicines. None of this replaces medical care.
Broken or already reactive skin
Nothing goes on it. The outer layer is the barrier that makes a percentage mean anything, and where it is broken there is neither. Sunburnt, freshly shaved or cracked skin is the same category. Wait until it is intact.
Animals in the house
An animal cannot leave a room you have filled and cannot tell you it would like to. Diffuse with a door open, keep runs short, and put nothing on an animal and nothing in its water without a veterinary surgeon’s direction.
The hot oils
Oregano, thyme, cinnamon bark, cassia and clove produce real heat on skin and can irritate it at ordinary dilutions. They go at 0.5% or less — one drop in 10 millilitres — on the soles of the feet. Peppermint sits alongside them for children, not adults. If something burns: carrier oil, generously, not water.
Everything above is useless in a cupboard. What separates a household that owns oils from one that uses them is three plain habits.
Use oils internally only if the label on your own bottle says they are for internal use; labelling differs by market. Dilute for topical use, keep oils away from eyes and inner ears, and keep them out of reach of children. If you are pregnant, nursing, under medical care or taking medication, speak to your healthcare practitioner before use. Nothing here is intended to diagnose, treat, cure or prevent any disease.
Where to go next
Lesson 7 of 21 · Essential Oils