"When [the hiccups] started, it was completely random, out of the blue, for no reason," said Sands, whose first bout of chronic hiccupping occurred in February 2007.
"In general, [hiccupping] is a sign of diaphragm-related problems," said Dr. Martin Makary, director of the Johns Hopkins Center for Surgical Outcomes Research, who pointed out that the muscle can contract irregularly due to irritation or an abnormality such as a hole.
But it quickly became clear that nothing worked to alleviate Sands' hiccups. After much medical testing, including head, chest and abdomen scans, doctors were unable to identify the source of Sands' chronic hiccups.
The only thing wrong was a damaged valve connecting Sands' esophagus to his stomach, a condition that he was born with and that caused him frequent heartburn and vomiting. Coupled with the hiccups, Sands has not been able to eat, sleep or perform as a guitarist and backup vocalist with his band, Ebullient.
"I can hiccup for 14 hours nonstop or I'll be free of them, but not free of them at all," Sands said.
When he is not actively hiccupping, Sands feels like he is about to hiccup at any moment, much like the tickle before a sneeze.
"I'm curled up in a ball on the floor, writhing around in pain, drinking water."
Sands had surgery this week to correct the faulty valve, but it had no effect on his condition.
BBC1 is working to develop a program featuring Sands as he travels across the United States seeking a cure for his hiccups.
Natalie Adler, 21, of Caulfield South, Melbourne, Australia, said she can sense the onset of her unusual condition -- and when she should start preparing for three days of darkness.
"The night before it sets in, my eyes get quite heavy and that is how I know it is coming," Adler told ABCNews.com.
Invariably, the next morning Adler finds herself unable to open her tightly shut eyes. The bouts generally last for about three days, after which she can open her eyes and once again see normally.
Adler has suffered from the condition for the last four years, she said. Doctors, both in Australia and the United States, are baffled as to the exact cause -- or indeed, whether her condition is physical or psychological.
"We're not really sure of the diagnosis," said Catherine Mancuso, an orthoptist who coordinated Adler's treatment plans at The Royal Victorian Eye and Ear Hospital in Melbourne, Australia.
"There's nothing that would cause symptoms of a woman to close her eyes for three days, and open her eyes for three days," said Dr. Dean Cestari, a neuro-ophthalmologist at the Massachusetts Eye and Ear Infirmary in Boston.
Cestari believes that at least part of Adler's condition may be attributed to a psychological condition that has manifested itself in a physical way.
"It can be hard, because sometimes these patients come in with real experiences. They aren't making this up," said Cestari. "But the mind converted a conflict into a physical manifestation."
For now, Adler receives Botox treatments to the muscles surrounding her eyes. The injections often help her to keep her eyes open, but she said that the effectiveness of the treatments is starting to wane.