Solanum nigrum
Solanaceae
Black Nightshade; Nightshade; Deadly Nightshade; Garden Nightshade; Common Nightshade; Hound’s Berry; Petty Morel; Wonderberry; Solanum nigrum; Solanum spp.
Steroidal glycoalkaloids and related Solanum alkaloids, including solanine, solamargine, solasonine, chaconine, and solanocapsine; saponins; and atropine-like substances. Unripe green berries and green plant parts are generally considered higher risk. Nitrates may also be a concern in grazing livestock exposed to Solanum nigrum under certain growing conditions.
Hypersalivation, drooling, inappetence, severe gastrointestinal upset, vomiting, abdominal pain, diarrhea, drowsiness, central nervous system depression, confusion, behavioral change, weakness, dilated pupils, slow heart rate, abnormal heart rhythm, fever, sweating, respiratory distress, collapse, and possible death in severe cases. Symptoms may be delayed for 6 to 12 hours after ingestion, particularly when glycoalkaloid exposure is significant.
The toxicity of Black Nightshade, Solanum nigrum, varies widely depending on the variety, plant maturity, plant part ingested, growing conditions, and the individual animal involved. This variability is one of the reasons Black Nightshade is a difficult plant to discuss in simple terms. In some contexts, certain ripe berries of some black nightshade forms have historically been treated as edible by humans after careful identification and preparation, while in a veterinary and pet-safety context the plant should be treated as toxic and unsafe for companion animals and livestock.
All parts of the plant can be poisonous, with the highest risk generally posed by the unripe green berries, green plant parts, and stressed or immature plant material. The plant contains toxic steroidal glycoalkaloids, including solanine, solamargine, solasonine, chaconine, and related Solanum alkaloids. ASPCA lists Black Nightshade, Solanum nigrum, as toxic to dogs, cats, and horses, with toxic principles identified as solanine, saponins, and atropine-like substances. Clinical signs listed for dogs, cats, and horses include hypersalivation, inappetence, severe gastrointestinal upset, diarrhea, drowsiness, central nervous system depression, confusion, behavioral change, weakness, dilated pupils, and slow heart rate.
The concentration of toxic glycoalkaloids can vary substantially between plants. The risk is influenced by the plant’s stage of growth, environmental stress, soil and growing conditions, plant variety, and whether the animal consumes leaves, stems, berries, or other plant material. Unripe green berries are particularly concerning because they may contain higher concentrations of toxic alkaloids than fully mature fruit. For pets and grazing animals, there is no practical reason to treat any part of the plant as safe.
Adding further risk to ingestion of the plant is that poisoning symptoms may be delayed for 6 to 12 hours after ingestion. This delay can create a false sense of security. A pet or livestock animal may appear normal shortly after eating the plant, while toxic compounds continue to irritate the gastrointestinal tract, affect the nervous system, or interfere with cardiovascular and respiratory function. By the time obvious clinical signs present, the window for simple early decontamination may already be narrowing.
Initial symptoms of toxicity may include confusion, drowsiness, behavioral change, fever, sweating, hypersalivation, inappetence, and severe gastrointestinal upset, including vomiting, abdominal pain, and diarrhea. Central nervous system depression, weakness, dilated pupils, slow heart rate, abnormal rhythm, collapse, or respiratory distress may occur in more serious exposures. Deaths reported from ingestion of Solanum nigrum plant parts have been attributed to cardiac arrhythmia and respiratory failure.
Nitrate toxicity from grazing the leaves of Solanum nigrum has also been reported as a cause of fatal livestock poisoning. This is especially relevant where livestock graze weedy areas, overgrazed fields, disturbed ground, fence lines, crop margins, or areas where Black Nightshade has become abundant. As with many toxic pasture weeds, the risk increases when desirable forage is limited or when animals are forced to consume plants they would normally avoid.
Because Black Nightshade is a Solanaceae plant and because common names are often used loosely, it should also be distinguished from other “nightshade” plants, including deadly nightshade, bittersweet nightshade, climbing nightshade, and other Solanum species. These plants may share overlapping clinical signs and toxic principles, but they are not necessarily identical in toxin concentration, palatability, or severity. For pet and livestock safety, botanical identification matters, but uncertainty should always be treated conservatively.
The practical rule is simple: Black Nightshade should not be allowed where pets, horses, livestock, rabbits, poultry, or other animals may chew leaves, berries, or stems. Any suspected ingestion should be taken seriously, especially if unripe berries were eaten, the amount is unknown, symptoms are delayed, or the animal begins showing gastrointestinal, neurologic, cardiac, or respiratory signs.
Immediate Response to Black Nightshade Ingestion
- Remove the Source: Prevent further ingestion by removing the animal from the plant, pasture, garden bed, berries, leaves, stems, clippings, or any area containing Black Nightshade or unidentified nightshade plants.
- Identify the Plant Part: Determine whether the animal ate leaves, stems, flowers, ripe berries, unripe green berries, or unknown plant material. Unripe green berries and green plant parts are generally more concerning.
- Remove Plant Material from the Mouth: If ingestion was recent and it is safe to do so, remove visible plant material from the mouth and flush the mouth thoroughly with water.
- Do Not Wait for Symptoms: Symptoms may be delayed for 6 to 12 hours after ingestion, so a normal appearance shortly after exposure does not rule out poisoning.
- Watch for Gastrointestinal and Neurologic Signs: Monitor for drooling, vomiting, abdominal pain, diarrhea, inappetence, drowsiness, confusion, behavioral change, weakness, dilated pupils, slow heart rate, abnormal rhythm, collapse, or respiratory distress.
- Contact Veterinary Help Promptly: Contact a veterinarian, emergency veterinary clinic, ASPCA Animal Poison Control, or Pet Poison Helpline if ingestion is suspected, if the amount is unknown, if unripe berries were eaten, if symptoms are present, or if the exposed animal is a cat, dog, horse, livestock animal, rabbit, poultry, young animal, elderly animal, pregnant animal, or medically fragile animal.
Inducing Vomiting and Decontamination
- Getting Plant Material Out Matters: If a dog has recently swallowed Black Nightshade, removing remaining plant material from the stomach may reduce continued exposure to glycoalkaloids and related Solanum toxins. Because clinical signs may be delayed, early decontamination can be especially important when ingestion is witnessed or strongly suspected.
- Inducing Vomiting in Dogs Only: If ingestion was recent and the dog is alert, breathing normally, able to swallow, and not showing weakness, collapse, severe depression, tremors, seizures, repeated vomiting, slow heart rate, abnormal rhythm, breathing difficulty, or neurologic signs, a veterinarian or animal poison-control professional may recommend inducing vomiting with fresh 3% hydrogen peroxide.
- Cat Warning: Hydrogen peroxide should not be used to induce vomiting in cats unless a veterinarian specifically directs it. Cats are more prone to irritation and complications from hydrogen peroxide, and home vomiting attempts may create more risk than benefit.
- Do Not Induce Vomiting in an Unstable Animal: Vomiting should not be attempted in any animal that is weak, collapsed, sedated, having trouble breathing, unable to swallow normally, already vomiting repeatedly, showing neurologic signs, showing cardiac signs, or otherwise unstable.
- Activated Charcoal: Activated charcoal is a valuable tool for binding ingested toxins in the stomach and intestinal tract, but it should be administered under veterinary or poison-control direction, especially if the animal is depressed, vomiting, weak, or at risk of aspiration.
- Veterinary Decontamination: In significant or high-risk cases, a veterinarian may consider gastric lavage, activated charcoal, cathartics, anti-nausea medication, respiratory support, or other decontamination and stabilization measures depending on the timing, amount, species, and clinical signs.
Respiratory, Cardiovascular, and Supportive Treatment
- No Specific Antidote: There is no specific antidote available for Black Nightshade poisoning, so treatment is mainly symptomatic and supportive.
- Respiratory Support: Because death in severe cases may occur from acute respiratory failure, respiratory support is a major priority when breathing becomes labored, shallow, irregular, or inadequate.
- Oxygen and Intubation: If the animal consumed a large amount and is suffering respiratory or cardiovascular distress, intubation and oxygen support may be necessary.
- Cardiovascular Support: Animals with slow heart rate, abnormal rhythm, low blood pressure, collapse, or cardiovascular compromise may require monitoring and veterinary-directed treatment, including vasopressors when clinically appropriate.
- Fluid and Electrolyte Replacement: Due to the severe gastrointestinal upset that may occur, fluid and electrolyte replacement may be necessary to correct dehydration, diarrhea-related losses, and shock risk.
- Seizure Control: Diazepam or other veterinary-directed medications may be used for control of convulsions or severe neurologic signs.
Livestock and Pasture Management
- Remove from Contaminated Areas: Grazing animals should be removed from pastures, fence lines, gardens, crop margins, disturbed soil, or overgrazed areas where Black Nightshade is present.
- Nitrate Risk: Nitrate toxicity from grazing Solanum nigrum leaves has been reported in livestock and should be considered when multiple animals are affected or when exposure involves heavy grazing of green plant material.
- Inspect Forage and Hay: Examine feed, hay, and pasture material for nightshade contamination, especially where weeds have been cut, baled, or mixed into feed.
- Prevent Access to Berries: Prevent animals from grazing or browsing plants with berries, especially unripe green berries, which are generally considered higher risk.
Prognosis and Recovery
- Variable Prognosis: Depending upon the amount of plant ingested, plant part consumed, toxin concentration, animal species, and time to treatment, prognosis may vary from good to poor.
- Minor Ingestion: In many cases of minor ingestion, especially when treatment occurs early and symptoms remain mild, the pet may make a full recovery in a matter of hours.
- Delayed Signs: Because signs may be delayed for 6 to 12 hours, animals should be watched closely even if they initially appear normal.
- Severe Cases: Prognosis is guarded to poor when respiratory distress, cardiovascular compromise, severe neurologic signs, arrhythmias, collapse, seizures, or respiratory failure develops.
- Prevention: Prevent further ingestion of the plant, remove Black Nightshade from areas accessible to pets and livestock, and contact a veterinarian promptly whenever exposure is suspected.