Humans can eat catnip, or more usefully, drink it. The same plant that sends a cat rolling around the kitchen is a mild, minty tea, and it has been used that way in Europe for centuries. You will not get the cat's reaction. You may get a slightly sleepy cup of something that tastes of grass and mint.
Use culinary-grade herb. The bag from the pet shop is not food.
What it does in people
Cats smell nepetalactone and go through a short, physical sequence. People swallow the plant, and the effect is closer to lemon balm or a weak valerian: a bit of calm, sometimes a bit of drowsiness, sometimes nothing much.
The traditional uses are the ones you would expect of a mint:
- An evening tea, because it has no caffeine and a mild sedative reputation
- An upset stomach, because it is carminative, which is the old word for reducing gas
- A restless evening, in the same way people reach for chamomile
The evidence is historical and anecdotal rather than clinical. Treat it as a herb tea, not as a treatment.
Pet-aisle catnip is the wrong bag
Catnip sold for cats is not produced as food. It can be dusty, mixed with stem, stored in conditions that would not pass a kitchen, and occasionally treated in ways you would not want in a mug. Buy dried catnip sold for tea, or grow your own and dry it yourself.
Fresh leaves from an organic plant in a pot are fine. Wash them. Do not harvest from a roadside or from a bed you cannot account for.
How to brew it
- Heat water to just off the boil, around 90–95°C. Rolling boil is harsher than it needs to be.
- One to two teaspoons of dried leaf, or a small handful of fresh, per mug.
- Pour, cover the cup, and leave it 10 to 15 minutes. Covering keeps the oils in the drink instead of in the room.
- Strain.
On its own it is grassy, a little woody, with a mint edge and a faint bitterness. Honey, lemon, or a pinch of peppermint make it easier to drink. That is taste, not efficacy.
Who should not drink it
Large amounts can mean a headache or nausea. Do not drink it and then drive if it makes you drowsy; for most people it will not, but it is a sedative herb.
Skip it if you are pregnant. Catnip has a reputation for stimulating uterine contractions, and there is no good reason to test that. Stop it at least two weeks before a planned surgery that involves anaesthesia, the same advice given for other herbs that slow the central nervous system.
Children, and anyone on prescribed sedatives, should not treat this as a casual experiment. A cup of culinary-grade tea is one thing. Treating the pet toy as an ingredient is another.
If you are brewing it for yourself, keep the jar on a high shelf. The cat will have its own opinions about an open bag of the same plant.