The toothache plant (Acmella oleracea) is a flowering plant native to Brazil. It has many names, including:

  • Spilanthes acmella
  • jambu
  • electric daisy
  • paracress
  • eyeball plant

The plant is related to the daisy, but it looks very different. It has round, yellow flowers with dark red spots in the center. These flowers, often called buzz buttons or Sichuan buttons, are actually clusters of many tiny flowers.

You can find the toothache plant in tropical and subtropical regions, including northern Australia, Africa, Sri Lanka, and southern and central India.

Traditionally, the plant is used for its medicinal benefits. Some of these effects have been proven by science. It’s commonly used for toothaches, but it’s also used for other issues like inflammation and gastrointestinal problems.

In some parts of the world, the toothache plant is used in food. It has a strong, bitter taste that adds a unique flavor to dishes.

Keep reading to learn more about the toothache plant, its potential side effects, and how to grow it.

There’s some scientific evidence that the toothache plant has medicinal benefits.

Toothaches

As the name suggests, the toothache plant is used to ease toothache pain.

When chewed, it has a numbing effect on the mouth. This local anesthetic effect is due to spilanthol, the plant’s main active ingredient, according to a 2020 review.

It also has plant compounds called flavonoids. The flavonoids reduce prostaglandins, which interfere with your perception of pain.

Stomatitis

The toothache plant is used to treat stomatitis or inflammation of the mouth. The condition can be painful, making it difficult to eat or drink.

The pain-relieving effect of spilanthol may help. The phytochemicals in Acmella oleracea, like spilanthol, also have anti-inflammatory effects that may help stomatitis, according to a 2024 review.

Dermatitis

Due to its anti-inflammatory properties, the toothache plant could relieve dermatitis. This condition occurs when the skin becomes inflamed and swollen.

A 2019 animal study specifically examined this benefit. The researchers found that spilanthol suppresses migration of inflammatory cells, creating an anti-inflammatory effect. This decreases the swelling seen in dermatitis.

Diuretic

The tropical plant is also a natural diuretic. Diuretics help your body get rid of excess fluid by making you pee more.

This effect was proven by a 2016 animal study on mice, which found that spilanthol increases urine output. The researchers determined that spilanthol targets cellular activities in the kidneys involved in urine production and water reabsorption.

Dry mouth

If your salivary glands don’t make enough saliva, you have what’s called dry mouth. It can lead to bad breath and dry, cracked lips.

The bitter flavor of the toothache plant can help. Its bitter taste comes from spilanthol, which can stimulate your salivary glands.

In Sri Lanka, the flower extract of the toothache plant is used for this purpose. A small 2017 study also found that toothpicks with spilanthol increase salivation in people with dry mouth.

Gastric ulcers

According to a 2021 animal study, the toothache plant may also help gastric ulcers. It contains a polysaccharide, or complex carbohydrate, called rhamnogalacturonan (RGal).

The researchers found that RGal increases cell growth and reduces inflammation, helping heal gastric ulcers.

When used as a flavoring or food, the toothache plant and its active ingredients are generally considered safe.

However, it can cause complications if the following scenarios apply to you:

  • You have an allergy to the daisy family: If you’re sensitive or allergic to daisy (Asteraceae) family, use caution.
  • You use diuretics: Since spilanthol is a natural diuretic, it’s important to avoid using it with diuretic drugs.
  • You have prostate cancer: The toothache plant might promote production of male hormones, which could interact with prostate cancer drugs. The risk is higher if you consume the plant at high doses.
  • You’re pregnant: High intake of the plant may lead to birth defects. You shouldn’t use it if you’re pregnant.

Always speak with a healthcare professional before trying the plant.

Depending on where you live, the toothache plant might be hard to find. Your best bet is to visit a nursery or find an online retailer that sells tropical plants.

If you prefer medicinal products that contain the toothache plant, check out places like:

  • health markets
  • apothecaries
  • herbal medicine shops
  • vitamin and supplement stores

Toothache plant products are often labeled as “Spilanthes.”

If you’d like to grow a toothache plant at home, follow these instructions:

  1. Use high-quality, well-draining soil.
  2. Start seeds indoors 4 to 6 weeks before last frost. Press into the soil without covering, then water.
  3. Keep the seeds moist until they germinate.
  4. Transplant young plants outside into 12-inch pots after last frost has passed. If planting in a garden bed, space them at least 12 inches apart.
  5. Water the plants every few days. Avoid overwatering.

You can expect your toothache plants to bloom between August and October.

Known for its round yellow flowers, the toothache plant has anesthetic and anti-inflammatory properties. The plant is also used as an herb or food in some parts of the world.

Use caution with this plant if you’re taking diuretics, pregnant, or allergic to the daisy family. The same goes if you have prostate cancer.

It’s possible to grow the toothache plant in garden beds or pots. It thrives during the warmer months, offering a colorful and unique touch to your home garden.