Black Nightshade Drug Interactions, Uses, Effectiveness, Safety & More

Black nightshade (Solanum nigrum) is a small flowering plant in the same family as tomatoes, potatoes, and peppers. It grows as a common weed across many parts of the world, including Europe, Asia, Africa, and the Americas. The plant produces small berries that may appear green, then ripen to a dark black or purple color.

In some cultures, the tender leaves are cooked and eaten as a leafy green vegetable, and fully ripe berries are sometimes eaten as food. Different parts of the plant also appear in various traditional medicine systems. However, the plant contains natural compounds that can be toxic, especially in the unripe berries and green parts.

Black nightshade contains a mix of plant compounds, including steroidal glycoalkaloids such as solanine and solasonine, as well as flavonoids and other antioxidants. The glycoalkaloids are the same general class of compounds that make unripe potatoes and green plant parts toxic.

In laboratory and animal research, extracts of the plant have shown antioxidant, anti-inflammatory, and other biological activities. Some lab studies have also looked at effects on cancer cells and the liver. It is important to understand that these are early, test-tube and animal findings only, and they do not tell us how the plant behaves in the human body.

The biggest concern with black nightshade is toxicity. The unripe (green) berries and the green parts of the plant can contain higher levels of toxic glycoalkaloids. Eating these can cause poisoning, and accidental poisoning—especially in children who eat the attractive berries—has been reported.

Fully ripe berries and properly cooked leaves are generally considered lower in these toxins and are eaten as food in some regions, but the toxin content can vary from plant to plant. Because it is hard to tell a safe plant from a more toxic one, casual foraging is risky.

Pregnancy and breastfeeding: There is not enough reliable safety information, and the potential for toxicity is a serious concern. You should avoid black nightshade during pregnancy and while breastfeeding. Children, older adults, and people with liver or kidney problems should also avoid it.

Eating toxic parts of the plant or too much of it can cause symptoms of glycoalkaloid poisoning, which may include nausea, vomiting, stomach pain, and diarrhea. More severe poisoning can lead to drowsiness, confusion, a fast or irregular heartbeat, trouble breathing, and in serious cases can be life-threatening.

If you or a child has eaten unripe berries or large amounts of the plant and feels unwell, seek medical care or contact a poison control center right away.

There is no established or standardized safe dose of black nightshade as a supplement. Because the toxin content varies and the line between a food amount and a toxic amount is unclear, no reliable medicinal dose can be given.

If you are considering any product that contains black nightshade, follow the product label exactly and speak with a pharmacist or doctor first. When it comes to wild plants, never guess at an amount or forage your own to use as medicine.