Agastache foeniculum

What is Agastache foeniculum?

Agastache foeniculum is a tall mint-family plant native to central and northern North America. Most people know it as anise hyssop. The leaves and purple flower spikes smell strongly of anise or licorice.

It is used mainly as a tea herb and a kitchen flavouring. Cooks add the leaves to desserts, drinks and salads. Beekeepers plant it for the honey.

In folk use it was a cough and cold tea. Today it is sold as loose dried leaf, as a tea blend, and as an essential oil.

Here is the honest verdict on the evidence. There are no good human trials of this plant for any health problem.

Long traditional use tells you people valued it. It does not prove the plant works, and it does not prove it is safe.

One point matters more than the rest. The essential oil is very high in estragole, a compound that caused tumours in rodents at high doses. The leaf tea is a far weaker product, but the oil should not be swallowed.

How does Agastache foeniculum work?

No one has shown how this plant acts in the human body. What follows is lab work, not proof of a health effect.

In test tubes, the essential oil slows the growth of some bacteria and fungi. That is common for strong-smelling mint-family oils. Whether it does anything useful inside a person is not known.

In test-tube chemistry tests, extracts mop up free radicals. This is often called antioxidant action. It is a result in a dish, not a measured benefit in people.

In animal and cell work, anethole and related anise-smelling compounds appear to relax gut muscle. This may be the reason anise-like herbs have long been drunk after meals. It has not been tested properly in humans with this plant.

The warm tea itself may soothe a sore throat. That effect comes from the heat and fluid as much as from the herb.

What forms does Agastache foeniculum come in?

Most people meet it as a drink or a flavouring, not as a supplement.

Common forms:

- Fresh leaves and flowers, used in cooking and in cold drinks. - Dried loose leaf for tea, sold alone or in blends.

- Tea bags, usually mixed with mint or lemon balm. - Honey made by bees working the flowers. - Essential oil, sold for scent and for soap and candle making.

Less common forms:

- Alcohol tinctures from small herb makers. - Dried herb capsules. These are rare and poorly standardised.

The essential oil is a different product from the tea, not a stronger version of it. It is highly concentrated. It is meant for scent, not for swallowing.

Where it comes from:

Several First Nations and Native American peoples used anise hyssop as a medicine plant. Written records come mainly from plant collectors in the 1800s and 1900s.

Reported traditional uses included:

- Leaf tea for coughs and chest colds. - Tea to raise a sweat during a fever.

- A sweetener for less pleasant medicine teas. - Dried leaves burned for scent in ceremony.

The Cree, Ojibwe and Lakota are among the peoples named in these accounts. The plant also spread into settler kitchen gardens, where it became a bee plant and a cooking herb.

These records describe past practice. They are not a recommendation to treat yourself, and the amounts and plant parts used were often not written down.

What does Agastache foeniculum help with?

• Cough and chest colds: This was the main traditional use of the leaf tea. There are no human trials testing it for cough. A warm drink does ease throat tickle for a while, but that is not specific to this plant. Do not rely on it for a chest infection.
• Sore throat: Folk use favoured a warm, sweet-smelling tea for a raw throat. No study has tested this. Any relief is likely short and mostly due to warm fluid. See a doctor if the pain is severe or you cannot swallow.
• Gas, bloating and mild indigestion: Anise-smelling herbs have long been drunk after meals across many cultures. In animal and cell work, anethole appears to relax gut muscle. Agastache foeniculum itself has not been tested in people for this. Treat it as a pleasant drink, not a treatment.
• Fever (as a sweating tea): Some traditional accounts used the hot tea to bring on a sweat during fever. There is no evidence that this shortens an illness or helps you recover. A high or lasting fever needs medical care.
• Use as a flavouring and sweet tea herb: This is the use with the firmest footing. The leaves taste of anise and make a caffeine-free tea. That is a food use, not a health claim.

Which foods are rich in Agastache foeniculum?

Anise hyssop is itself a food herb. Fresh leaves go into salads, fruit dishes, baked goods and cold drinks. Honey from its flowers is sold as anise hyssop honey. None of these food uses carry a proven health benefit.

What are the side effects of Agastache foeniculum?

• Mouth or throat irritation from a very strong tea
• Mild nausea or heartburn
• Allergic rash, itching or swelling in people sensitive to mint-family plants
• Skin irritation or burning from the undiluted essential oil
• Possible drowsiness or stomach upset if large amounts are drunk

Good to know:

Reported side effects are rare and mild at food-level amounts. Most reports are of allergy or of skin irritation from the oil. The serious concern is not a side effect you would feel.

It is the estragole in the essential oil, which caused liver tumours in rodents at high doses. That risk belongs to the concentrated oil, not to an occasional cup of tea.

How much Agastache foeniculum should you take?

• Recommended daily: This page gives no personal dose. For context only: tea labels usually suggest about 1 to 2 grams of dried leaf per cup, up to two or three cups a day. That is a food-style amount, and it matches how the herb is normally drunk. No studied or proven dose exists for any health purpose. No safe swallowed amount of the essential oil can be given, because of its estragole content, so none is listed here.
• Best time of day: Timing does not matter for safety, so suit yourself. The tea has no caffeine, so evening use is fine. People who drink it for gas usually take it after a meal.
• With or without food: Either is fine. Taken for gas or fullness, it is usually drunk after eating. A strong tea on an empty stomach may feel sharp for some people.
• Time to effect: Be realistic: it may do nothing at all. Any soothing from a warm drink is felt while you drink it and fades soon after. There is no evidence of a build-up effect over days or weeks. If you expect a measurable health change, the honest answer is that none has been shown.
• How long to take it: No trial has tested long-term use, so no safe length of use is known. Occasional use as a tea, like any kitchen herb, is the pattern with the longest track record. Heavy daily use over months has not been studied and is not supported. If you are drinking it for a symptom and nothing changes within a week or two, stop and get the problem looked at.