Benedict Cumberbatch’s Nicotine Poisoning

Actor Benedict Cumberbatch has been quite busy lately. He has four movies awaiting release: “Doctor Strange in the Multiverse of Madness,” “Spider-Man: No Way Home,” “The Electrical Life of Louis Wain,” and “The Power of the Dog.” It was Cumberbatch’s dedication to immersing himself in this last film’s character that got him into a bit of health trouble.

“The Power of the Dog,” based on the 1967 novel by Thomas Savage, is a story about an early 20th century Montana rancher, Phil Burbank, who torments the wife of his younger brother, George. Phil is described as “a great reader, a taxidermist, skilled at braiding rawhide and horsehair, a solver of chess problems, a smith and metalworker, a collector of arrowheads (even fashioning arrowheads himself with greater skill than any Indian), a banjo player, a fine writer, a builder of hay-stacking beaver-slide derricks, a vivid conversationalist.”

Cumberbatch immediately went to work to learn these skills, making horseshoes, carving wood into both large and small objects, braiding, whistling, stacking hay, and taking banjo lessons. In an interview with Esquire UK, Cumberbatch revealed that he failed to master the banjo: “I really wanted to become world class at the banjo and I’m very much not. I’m very far off.”

Cumberbatch also took on some of Phil’s bad habits. First, Burbank seldom washed, so Cumberbatch didn’t either: “I wanted that layer of stink on me. I wanted people in the room to know what I smelt like.” Phil was also a heavy smoker. Cumberbatch hand-rolled the cigarettes and smoked them all, telling the magazine: “That was really hard. Filterless rollies, just take after take after take. I gave myself nicotine poisoning three times. When you have to smoke a lot, it genuinely is horrible.”

Nicotine is a chiral alkaloid that is naturally produced by the nightshade family of plants, most notable of which is tobacco. The tobacco plant is indigenous to the Americas and has been used as a medicine and stimulant for at least 2,000 years. Nicotine constitutes approximately 0.6% to 3.0% of the dry weight of tobacco.

According to the National Institute on Drug Abuse, the cigarette is a very efficient and highly engineered drug-delivery system for nicotine. By inhaling tobacco smoke, the average smoker takes in 1 to 2 mg of nicotine per cigarette. When tobacco is smoked, nicotine rapidly reaches peak levels in the bloodstream and enters the brain.

A typical smoker will take 10 puffs on a cigarette over the roughly 5 minutes that the cigarette is lit. Thus, a person who smokes about one pack (20 cigarettes) daily gets 200 “hits” of nicotine to the brain each day. Among those who do not inhale the smoke — such as cigar and pipe smokers and smokeless tobacco users — nicotine is absorbed through mucous membranes in the mouth and reaches peak blood and brain levels more slowly.

Immediately after exposure to nicotine, there is a “kick” caused in part by the drug’s stimulation of the adrenal glands and resulting discharge of epinephrine. The rush of adrenaline stimulates the body and causes an increase in blood pressure, respiration, and heart rate.

Nicotine is addictive. A transient surge of endorphins in the reward circuits of the brain causes a slight, brief euphoria when nicotine is administered. This surge is much briefer than the “high” associated with other drugs. However, like other abused drugs, nicotine increases levels of the neurotransmitter dopamine in these reward circuits, which reinforces the behavior of taking the drug.

Repeated exposure alters these circuits’ sensitivity to dopamine and leads to changes in other brain circuits involved in learning, stress, and self-control. For many tobacco users, the long-term brain changes induced by continued nicotine exposure result in addiction, which involves withdrawal symptoms when not smoking, as well as difficulty adhering to the resolution to quit.

Nicotine Poisoning

Nicotine poisoning can occur with any form of nicotine-cigarette smoking, e-cigarettes, chewing tobacco and snuff, and even nicotine patches. Nicotine overdose is unlikely with tobacco cigarettes, since the body only absorbs about one-tenth of the nicotine in a cigarette. Overdose due to nicotine patches is also unlikely unless instructions are not followed. E-cigarettes pose a bigger risk. They use a battery to heat liquid nicotine in a cartridge for subsequent inhalation. Ingestion of this liquid can be toxic.

Children, young people, and pets are smaller and more susceptible to nicotine poisoning at lower doses. There is enough nicotine in a cigarette butt to harm a small child who might eat one. An older child experimenting with chewing tobacco can also take a toxic dose. Liquid nicotine from e-cigarettes often comes in colorful packages with candy flavors, which might entice a toddler to try it.

The symptoms of nicotine poisoning occur in two phases. Early symptoms of poisoning occur in the first 15 minutes to 1 hour, and include:

These symptoms can last up to 1 hour for mild intoxication to 24 hours for severe intoxication. In the second phase, which can occur 30 minutes to 4 hours later, symptoms include:

• Slowing of the heart rate

Treatments include supportive hydration, cardiorespiratory monitoring, and seizure control.

What Is the Lethal Dose of Nicotine?

The CDC and others have said that the lethal dose of nicotine is 60 mg or less. However, according to a 2014 article published in Archives of Toxicology, there are countless cases who have survived consumption of far larger doses.

The article disputed that 1 to 4 mg of oral nicotine can cause some of the severe symptoms noted, such as seizures and loss of consciousness.

A 2005 paper supported the assertion that we should stop using the 60-mg dose as the definition of lethal, recalling a patient who routinely ingested 7 to 20 cigarettes a day and had only mild symptoms of nicotine intoxication.

“Nicotine is a toxic compound that should be handled with care, but the frequent warnings of potential fatalities caused by ingestion of small amounts of tobacco products or diluted nicotine-containing solutions are unjustified and need to be revised in light of overwhelming data indicating that more than 0.5 g of oral nicotine is required to kill an adult,” the 2014 paper concluded.

Michele R. Berman, MD, is a pediatrician-turned-medical journalist. She trained at Johns Hopkins, Washington University in St. Louis, and St. Louis Children’s Hospital. Her mission is both journalistic and educational: to report on common diseases affecting uncommon people and summarize the evidence-based medicine behind the headlines.