I've had malignant cancer. Took 8 months of chemo and radiation. Lots of throwing up and feeling like shit, but also a lot of sleeping (I usually slept around 18 hours a day, getting up only to eat or puke or use toilet). It sucks, no lie, but then again, I only lost fifty pounds and I did survive, so I didn't see the worst of it. Some of my friends at the cancer center didn't make it and not all of them were in pain. Mostly it was just being tired all the time and the suffering from the chemo side effects.
However, there are a couple of cancers that I can think of that would be most terrible: metastatic bone cancer with base-of-skull syndrome (unimaginable headaches that never let up), and pancreatic cancer (abdominal pain beyond description). Neither condition treated very successfully with meds.
Worst way to die other than that? Three or four ways IMO:
Rabies--Not kidding at all--also called hydrophobia. Imagine this: your throat and mouth get so sore and painful that even the idea of drinking makes you cringe and scream. A week to 10 days later with little or no sleep you die from asphyxiation--miserably thirsty and in terrible pain.
Tetanus--your erector spinae and interspinous muscles contract so hard that the back of your head could touch your rear end (they've been known to cut the muscles to save you pain). However, the rest of your muscles are constantly in tonic spasm.
I second the one for Lou Gehrig's disease, and then add my own that's much like it: Severe Huntington's disease--you begin losing voluntary control of your body. Before long you can't really move or do much of anything except just lay there hardly blinking your eyes, living several years this way until the merciful end. I've seen it in person...not pretty.
Any of the hemmorrhagic fevers such as Monkeypox, Marburg, Ebola or Hantavirus. We've all seen the movie...a prof of mine said that was pretty accurate and usually slower.
Here one I learned of from case studies in pathology that would be rough and earn horrible mention:
Abdomino-thoracic gangrene caused by the Candiru catfish...this little thing lives in the waters of South American rivers and is tiny enough to swim up a person's urethra. It can lodge there and die causing tissue death and gangrene of the sex organs and then spreading to the nearby abdomen if treatment is not sought. Seems like I remember reading that he lived long enough to see "it" fall off. This unfortunate individual didn't get medical help in time and not only lost his manhood, but lost his life.
Now I'll go have nightmares and claim to be an adult.
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