Belladonna, also known as deadly nightshade, has been used for centuries as a cosmetic, a medicine, and a poison. Today, its primary medical value comes from the compounds extracted from its roots, leaves, and berries, which are used in prescription medications for digestive disorders and in eye drops for pupil dilation. It also appears in homeopathic products, though these have drawn significant safety warnings from the FDA.
How Belladonna Works in the Body
The plant contains a group of chemicals called tropane alkaloids, primarily atropine, hyoscyamine, and scopolamine. These compounds block a chemical messenger called acetylcholine, which your nervous system uses to control involuntary functions like digestion, heart rate, saliva production, and the muscles in your eyes. By blocking acetylcholine, belladonna alkaloids relax smooth muscles, slow gut movement, reduce secretions, and dilate the pupils.
This blocking effect is why belladonna-derived drugs can treat such different-seeming conditions. The same basic mechanism that calms an overactive intestine also opens up the pupil for an eye exam.
Digestive and Gastrointestinal Uses
The most common modern pharmaceutical use of belladonna alkaloids is for cramping and spasms in the digestive tract. Prescription combinations of belladonna alkaloids with phenobarbital (a mild sedative) are used to relieve pain from irritable bowel syndrome, spastic colon, and peptic ulcers. These medications work by slowing the motion of the stomach and intestines and reducing the secretion of stomach acid and other digestive fluids.
These prescriptions are typically taken three or four times a day, 30 minutes before meals and at bedtime. Slow-release versions are taken two or three times daily. Older adults generally need lower doses, since higher amounts don’t improve effectiveness and raise the risk of side effects like dry mouth, blurred vision, and confusion.
Eye Exams and Surgery
Atropine, the most well-known compound from belladonna, is still used by eye doctors to dilate the pupils before examinations and certain surgeries. Atropine eye drops at a 1% concentration are applied about 40 minutes before the procedure. The effect is notably long-lasting: pupil dilation, light sensitivity, and blurred vision can persist for up to two weeks in a normal eye, which is much longer than the dilation drops most people experience at a routine eye appointment.
This use of belladonna has the longest history of any. The name itself means “beautiful woman” in Italian, a reference to Renaissance women who dropped belladonna extract into their eyes to enlarge their pupils, which was considered attractive at the time.
Historical and Discontinued Uses
Belladonna’s medical history stretches back centuries. In 1803, the Edinburgh physician Andrew Duncan documented using powdered belladonna leaves and roots for epilepsy, mania, and melancholy. By the 1950s, belladonna plasters were sold over the counter in the UK for conditions ranging from rheumatism to pulmonary tuberculosis. These products have long since disappeared from pharmacy shelves, and most of these historical uses have no place in modern medicine.
Belladonna in Homeopathic Products
Belladonna is one of the more common ingredients in homeopathic remedies. Products labeled “Belladonna 30C” (a standard homeopathic dilution) are marketed for sudden fevers up to 102°F accompanied by sweating, a flushed face, and sensitivity to light, noise, and touch. In homeopathic theory, the plant material is diluted so many times that virtually none of the original substance remains, which is why mainstream medicine considers these products implausible as treatments.
More importantly, some homeopathic belladonna products have proven genuinely dangerous. The FDA issued repeated warnings between 2016 and 2017 about homeopathic teething tablets containing belladonna, sold by brands including Hyland’s and CVS. Testing revealed that the actual levels of atropine and scopolamine in these tablets varied wildly from one tablet to the next and, in some cases, far exceeded the amounts stated on the label. The inconsistent manufacturing meant that infants could receive unpredictable doses of a potent toxin. Hyland’s voluntarily recalled its teething tablets nationwide in April 2017, and the FDA issued warning letters to several other homeopathic manufacturers that same year. The agency urged consumers to dispose of any homeopathic teething products containing belladonna.
Why Belladonna Is Dangerous in Raw Form
Belladonna is called “deadly nightshade” for good reason. Every part of the plant is toxic, and the berries are especially dangerous because they look appealing and taste mildly sweet. Poisoning symptoms follow a predictable pattern driven by the same acetylcholine-blocking mechanism that makes the plant medically useful, just in uncontrolled amounts.
Early signs include dry mouth, dilated pupils, and a rapid heartbeat. As toxicity progresses, symptoms escalate to hallucinations, delirium, agitation, and confusion. Body temperature rises. Breathing slows. In severe cases, poisoning can lead to paralysis, dangerously low blood pressure, and shock. The classic medical mnemonic for anticholinergic poisoning captures it well: “blind as a bat, dry as a bone, red as a beet, mad as a hatter, hot as a hare.”
Children are at the highest risk because it takes far less plant material to cause serious harm in a small body. Even a handful of berries can be dangerous for a young child.
Pharmaceutical vs. Plant-Based Forms
The critical difference between belladonna as a prescription drug and belladonna as a plant or unregulated product is dosage control. Pharmaceutical atropine and hyoscyamine are manufactured at precise, consistent concentrations. The raw plant, by contrast, varies enormously in alkaloid content depending on the growing conditions, the part of the plant, and the time of harvest. This unpredictability is exactly what the FDA found in the teething tablet recalls: even products that were supposed to contain standardized amounts didn’t.
Belladonna extracts, tinctures, and supplements sold outside the pharmaceutical system carry this same risk of inconsistent potency. There is no safe way to self-dose with raw or minimally processed belladonna, and no herbal use of the plant that modern medicine considers advisable.