On day three of Lowell Cauffiel's final detox from alcohol, a giant rabbit in a tuxedo and top hat tapped on the window of his second-floor bedroom.

Cauffiel, a bestselling true crime author, Hollywood screenwriter and producer purposely didn't go to rehab 34 years ago. When he abruptly stopped drinking two fifths of bourbon a day, he wanted to experience the full effect of withdrawal.

The week-long process started with the feeling that his "guts were being pulled out." He shook. He sweat. He suffered some very vivid hallucinations.

"I knew it was going to be rough, but I wanted to use it as a motivation to stay sober," Cauffiel says.

It was, and it worked. Cauffiel never took another drink.

But he could have killed himself.

Doctors say alcohol is often the most dangerous substance for the body to withdraw from – and still more so, when attempted without medical supervision.

About 16 million people in the United States have alcohol use disorder, which the National Institutes of Alcohol Abuse and Alcoholism define as "compulsive alcohol use, loss of control over alcohol intake, and a negative emotional state when not using."

For those experiencing the most serious symptom of withdrawal – the shaking, shivering, sweating and confusion of delirium tremens, or the DTs – the death rate has been estimated as high as 4 percent, or 1 in 25.

Of patients admitted to one hospital in Spain with alcohol withdrawal syndrome from 1987 to 2003, a research team there found, 6.6 percent died. That's roughly 1 in 15.

The Centers for Disease Control and Prevention counted 831 deaths in 2016 that could be characterized as related to alcohol withdrawal. The National Institutes of Alcohol Abuse and Alcoholism do not have an estimate of deaths from alcohol detox.

One recent casualty was the actor Nelsan Ellis, a star of the HBO series True Blood, who died last year from complications of alcohol withdrawal, according to his family. His father said he “was ashamed of his addiction and thus was reluctant to talk about it during his life."

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Total alcohol deaths – through cancer, liver cirrhosis, pancreatitis, suicide and other causes – increased 35 percent from 2007 to 2017. The greatest increases were among people over 30 and women, who saw an 85 percent jump.

There was also a significant increase in emergency room visits related to binge drinking.

Along with patching up injuries and pumping fluid out of the stomachs of those addicted to alcohol, hospitals regularly have to deal with people going into abrupt withdrawal after they're admitted.

The danger of withdrawal from alcohol, as from other drugs, "has to do with the body's response to the extreme changes in the chemical processes going on in the brain and the rest of the body," psychologist Adi Jaffe wrote in Psychology Today.

Compounding the risk is that few people are honest with their doctors about how much alcohol they drink.

Dr. Malissa Barbosa, area director at CleanSlate addiction treatment centers in Orlando, says she typically assumes twice the amount patients tell her, to be safe.

Barbosa, a former primary care doctor in rural Pennsylvania, recalls a typical case.

A patient wasn't "very open about their alcohol abuse," she says. The patient had hip surgery – and then the DTs set in. The patient ended up in intensive care.

Delirium tremens typically starts 48 to 72 hours after the last drink. Patients suffer confusion, a racing heart beat, high blood pressure, fever and heavy sweating. In extreme cases, delusion, violent shaking and visual, audio and tactile hallucinations – the sensation of bugs crawling on the skin – and even seizures.

When Susan Moore's father was hospitalized in the mid-1970s for a minor surgery, she says, he was given a shot of whiskey each morning and evening. Doctors wanted to prevent a deadly detox.

The drinking ultimately killed him in 1996, the New Mexico woman says. The death certificate even said "alcoholism."

Moore, now 72, quit drinking in 1988. Her husband refused to stop, she says, and they divorced.

Around 2004, she says, her ex-husband was undergoing an angioplasty surgery when he went into alcohol withdrawal. He was put in a medical coma.

Within two months, his family says, he was drinking again. He died in 2014 at 65 of "chronic alcoholism," according to Lynda Moore, the couple's daughter.

Lynda Moore, 48, sent her mother a bouquet in August with a balloon saying "I'm grateful" to mark the anniversary of her mother's sobriety.

"She never forgets it and is very supportive and understands the struggle well," Susan Moore says. "She has borne a lot."

Even people who drink as little as two glasses of wine a night over many years can experience withdrawal symptoms when they stop, Barbosa says. People who drink four or more drinks a night should seek medical help when attempting to stop, she says.

Less extreme withdrawal symptoms include anxiety, shaky hands, headache, nausea, vomiting, insomnia and sweating. Those symptoms can be mistaken for a virus, Barbosa warns, which could lead people to miss the onset of withdrawal.

Some people don’t let even an hour go by without taking a drink. For these heavy drinkers, physicians say, quitting requires inpatient detox.

"I had already known my drinking was way out of control, but I didn’t know I would have died from withdrawals without medical detox," says Erin Ranta, 40. "Still in denial, I brought in my workaholic ways in detox and secured a job when I was discharged so instead of inpatient, I thought I could do it with outpatient."

It didn't work. The New York City woman would take Ubers to pick up her first of two or three pints of vodka in the morning and drank throughout the day before presenting herself for outpatient treatment.

Ranta says she ended each day blacked out: "My husband would find the wreckage of me hanging in by the thinnest thread."

Finally, she got so sick, she had no choice but to enter inpatient detox when she visited the hospital for symptoms of liver disease caused by her drinking.

She almost died multiple times, she says. A priest once talked to her about giving her last rites.

"I couldn’t have survived without medical detox, even though they are the most hellacious days I recall," says Ranta.

About 18 months after moving to New York, Ranta is sober, working as a Pilates instructor and happy with her life. She participates in the Instagram #plankanywhere trend by dropping to the Pilates push up position and posting a picture.

A few decades ago, hospitals kept alcoholic beverages on their prescription drug formulary to stabilize patients' blood-alcohol levels so they could be operated on, Barbosa says.

Dr. Robert Holbrook Smith – the "Dr. Bob" who co-founded Alcoholics Anonymous with Bill Wilson – is said to have drunk one last beer to steady his hands to perform a surgery three days after he started detoxing from a week-long binge and blackout.

After the surgery, the detoxification process began again. Doctors tapered Smith off of alcohol and fed him a diet of sauerkraut, tomato juice, and Karo syrup.

Patients today are typically treated with a combination of the vitamin Thiamine, a benzodiazepine such as Librium, Xanax or Ativan, and Depakote to prevent seizures.

Michelle Dion is the nurse supervisor for the Crossroad Addiction Recovery program at David Lawrence Center in Naples, Florida. Some patients come in with such a high blood-alcohol count, she says, that they have to be medically cleared for admittance.

A patient might have a blood-alcohol count of 0.19 even if he or she hasn't had a drink in 12 hours, she says. She describes a typical person with alcohol use disorder showing up "sweaty, anxious, with tremors, red in the face, with their blood pressure elevated, nauseous and with a feeling of impending doom."

Injections of Ativan help lower anxiety until the BAC is zero, she says.

Dr. Anthony Marchetti is medical director of the emergency department at Upson Regional Medical Center in Thomaston, Georgia.

More important than the number of drinks a person has a day, he says, is how many times a patient has gone through withdrawal before.

He says the risks become greater over time because drinking heavily every day causes permanent changes in the brain.

That's why it's unsafe for the heaviest drinkers to try to detox by themselves, Marchetti says. It has to be done more gradually than people realize.

"Almost everyone who tries to do it (alone) breaks through and has a seizure or some other complication from too-rapid withdrawal" he says.

As for Cauffiel, he went through his dramatic 1984 detox in his then-1-year-old son's room, he says, because he had been "banned from the marital bed."

After he saw what he thought was Harvey from the Jimmy Stewart movie at the window, he turned to his son.

The boy was standing up in his crib, holding onto the side. As Cauffiel watched, he says, his son turned into "Godzilla breathing fire out of his mouth."

Instead of seeking medical care, Cauffiel decided to pull the covers over this head and sweat it out – literally.

"I was putting my life at risk without a managed detox, I found out later," says Cauffiel. "Clearly it was a bad idea."

Ranta agrees. One of the reasons detox can be so deadly, she says, is that it's "a problem that so many hide."

“I’m lucky to have survived," Ranta says.

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