It did seem to reduce the risk of major heart attacks, but at the expense of major bleeding problems.

FORBES: Why Xarelto for ACS was doomed to fail

Some patients react badly to long-term painkiller use, suffering gastric bleeding and liver problems - and there is no guarantee that the benefits to one group of patients would outweigh the risks to another.

BBC: Aspirin

Professor Andrew Shennan, consultant obstetrician at St Thomas' Hospital in London and spokesperson for baby charity Tommy's, said problems with bleeding in pregnancy were a daily occurrence for obstetricians.

BBC: NEWS | Health | Caesarean link to placenta risk

But it has run into quality problems before that included bleeding colors on some tops.

WSJ: Lululemon Black Yoga Pants Make Comeback After Recall

In addition to the problem with bright colors bleeding, the company had transparency problems with some colors of swimwear shipped for last spring as well as a subset of light colored pants, Mr. Buss said.

WSJ: Yoga-Pants Supplier Says Lululemon Stretches Truth

Moreover, he says, the trial excluded patients at high risk for bleeding, such as those with central nervous system tumors or vascular problems.

FORBES: Genentech's Rite Of Spring

Mileson also talks of his own health problems, an operation following a burst bowel and internal bleeding forcing him away from the club from July until the end of last year.

BBC: SPORT | Football | My Club | Gretna | Worn-out Alexander explains exit

One 80-year-old patient died after suffering liver problems that may have been caused by Exanta, but the culprit may have been bleeding caused by other drugs.

FORBES: Replacing Coumadin