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Crucifixion -

Most of us associate crucifixion with the death of Jesus Christ, but this type of torture goes back to about the 6th century BCE.

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Crucifixion - While some artists depict Christ hanging from the cross in a somewhat peaceful manner, this type of death is indeed extremely painful. So much so that the word "excruciating" actually comes from "crucifixion."

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Crucifixion -

While most images depict nails through the palms of the hands, these are historically incorrect. The nails would instead go through the wrists, hitting the median nerve, which is incredibly painful. Not to mention all the insects that would irritate the wounds even more.

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Lethal injection -

This form of execution is supposed to be less painful when compared to other methods, but this isn't always the case.

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Lethal injection -

The most used protocol once included three drugs: a barbiturate and anesthetic, a muscle relaxant, and finally a drug to stop the person's heart. But this three-drug protocol was abandoned by some justice systems, in favor of single drugs. These, however, can make the pain last for minutes to hours, until the person dies.

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Lethal injection -

Many of these drugs will make the person relax, but they are not anesthetics, so the pain is not addressed. For instance, extreme pulmonary edema has been found in autopsies of executed prisoners.

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Drowning -

While it doesn't take forever, the process of drowning can be quite painful. To begin with, a person who is drowning is usually panicking, which leads to hyperventilation. But instead of air, the person will breathe in water.

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Drowning -

This will lead to a vocal cord spasm known as laryngospasm. But what causes the most pain is breathing in the water. Even for those who survive, their lungs remain in a state of pain for sometime.

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Electrocution -

Many of us have experienced small electric shocks, and they sure can be painful, but dying by electrocution is a whole different ball game.

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Electrocution -

When a powerful enough electric charge hits a person, their muscles seize, bones break, the skin swells up, and even eyeballs can pop out of their sockets. The whole process is excruciating.

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Burning -

If the thought of burning to death makes you cringe, there is a good reason for it: it's absolutely horrific. Our skin has numerous nerves, so the pain felt when these burn is very intense.

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Burning -

Not to mention the pain of breathing in smoke and hot air, that will not only make one choke but also burn everything on its way. It is indeed agonizing.

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Burning -

If you've ever wondered how lava might kill you, here's a summary. Your skin would boil and you'd go into instant rigor mortis (stiffening of the body). Not to mention that your brain might also boil, cracking your skull.

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Freezing -

Freezing to death is not as still and peaceful as it might sound. In fact, it's quite the opposite. Hypothermia will make a person shiver uncontrollably in the first stages.

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Freezing -

This will then be followed by muscle stiffness and brain malfunction. As your body tries to supply blood to your vital organs, the extremities will become painful. Frostbite then can cause a burning sensation. Overall, freezing is definitely not a pain-free way to die.

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Heart attack -

Unlike other causes of death on this list, the excruciating pain some people go through usually occurs right before the person has a heart attack. The warning signs can be very painful indeed.

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Heart attack -

There is usually pain radiating to the arm, jaw, neck, and back. Not to mention the crushing pressure felt on the chest, which is commonly described as if an elephant was sitting on your chest.

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Radiation -

One of the scariest things about radiation is that it is invisible and in the right doses fatal. But what actually happens when you suffer acute radiation syndrome (ARS)? To begin with, it damages both tissue and genetic material.

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Radiation -

This then translates into a number of health problems that impact the immune system. These eventually lead to serious complications such as the collapse of the circulatory system and, ultimately, death.

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Pancreatic cancer -

From nerve pain to bone damage, and treatment side effects, dying of cancer can be very painful, and pancreatic cancer is arguably the worst when it comes to pain.

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Pancreatic cancer -

Pancreatic cancer can cause a great deal of pain when it presses against the nerves around the area. This causes agonizing abdominal and back pain. Intestinal blockages can also occur, as well as referred soft-tissue pain in other parts of the body.

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Boomslang -

A boomslang is a snake, and a very poisonous one at that. This means, of course, that being bitten by one will cause a very painful death.

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Boomslang -

How does the venom kill you? Through hemorrhages. Essentially victims will bleed severely, internally. Then, uncontrollable shaking will set in, as well as nausea and high fever. It is indeed a painful death.

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Decompression sickness -

When divers go to into deep waters, they breathe compressed air that is much richer in oxygen and nitrogen than the one they'd breathe on the surface.

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Decompression sickness -

The problem is that the nitrogen accumulates, and if divers return to the surface too quickly, the nitrogen will expand and form bubbles, which affect the entire body. Decompression sickness, also known as barotrauma, or the bends, can be very painful and lead to death.

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Chlorine trifluoride (ClF3) -

Chlorine trifluoride (ClF3) was first discovered in the 1930s. It's a very reactive liquid that pretty much burns everything it comes into contact with.

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Chlorine trifluoride (ClF3) -

If you're wondering what exposure to ClF3 would look like, scientist Paul Doherty explains: "The chlorine will turn your bones to gelatin — your fingers will turn from rods into little rounded stubs." Ouch!

Sources: (Grunge) 

See also: Leading causes of death in the US by age group

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