NSAIDs, such as Advil, Motrin, Naprosyn, Aleve and ibuprofen, are taken like candy in America and much of the rest of the world as well. Yet few people realize how incredibly dangerous these drugs can be. It is no exaggeration to say that they are dangerous and can kill both you and your sex life.
What is particularly tragic about NSAIDs is that they are so universally accepted in our (American at least) society. Every supermarket and drugstore has almost an entire shelf filled with different preparations of these drugs. How could something be bad that is common, right?
Furthermore, it is well-known that many athletes take NSAIDs as if they were vitamins to supposedly help with healing, soreness and recovery. In fact, NBA players Alonzo Mourning and Sean Eliot, are even mentioned in one Medscape article , because they suffered the beginnings of renal failure due to their significant NSAID consumption during the season. The damage was so severe that they required a kidney replacement. (NOTE: Athletes should also read the above Medscape article for information regarding how NSAIDs are known for actually slowing recovery and other athletes that have suffered damage.)
These athletes are generally taking full dosages for extended periods of time. However, below I have listed three ways that NSAIDs can cause you major damage or even kill you with much smaller dosages:
1. Erectile Dysfunction. One 2006 study found that men using NSAIDs had almost double the rate of erectile dysfunction compared to those who were not.  Erectile dysfunction is a common side effect of these drugs and you should warn your woman as well: they can affect her libido and sexual function just as much.
2. Stroke. Stroke has long been suspected as a possible side effect of NSAID use and a recent Taiwanese study verified this forcefully. They studied all the common NSAIDs and found that almost all of them increased the risk of stroke by 20-90 percent.  One NSAID was even found to more than double the risk! And, by the way, NSAIDs increased the risk both for the common kind of stroke, ischemic, that destroys a part of the brain and can leave one partially paralyzed, and the less common kind, hemmorhagic, which results in nasty bleeding on the brain. The latter can even result in an excruciating aneurysm.
3. GI Bleeds and Stomach Ulcers. Many studies have documented the fact that ulcers are a common side effect of NSAID use. These drugs are extemely hard on the GI tract. In fact, I have one close relative who had a duodenal ulcer, which allowed fecal matter into the abdominal cavity resulting in the beginnings of septic shock, very likely resulting from consistent NSAID use. Researchers have recently documented multiple pathways to GI damage. 
4. Heart Attack. One recent study found that NSAIDs increased the risk of heart attack by 33%! This comes, by the way, from a monstrous analysis of many studies. Commentators have noted that there really are not safe long term pain medications. (Naproxen may actually be heart attack helpful, but it is the one exception. Discuss with your doctor.)
5. Reduction in Vitamin C Levels. If #1-4 aren't enough, then keep in mind that NSAIDs also lower Vitamin C levels and taking Vitamin C can casue the levels of the NSAID to increase. This University of Maryland Medical Center discussion explains why:
"Both aspirin and NSAIDs can lower the amount of vitamin C in the body because they cause more of the vitamin to be lost in urine. In addition, high doses of vitamin C can cause more of these drugs to stay in the body, raising the levels in your blood...If you regularly take aspirin or NSAIDs, talk to your doctor before taking more than the recommended daily allowance of vitamin C." 
6. Kidney Damage and Failure. Originally, it was thought that NSAIDs were only hard on patients with existing kidney disease. However, some subsequent research has cast doubts on the original optimism. For example, some of the older esimates were that it would take a very large amount of NSAID usage over many years to cause overt kidney damage. For example, check out this calculation:
"It is estimated that ingesting 10 kilograms of NSAIDs over a lifetime can cause direct kidney damage. Hence, if you take five Advil per day (5 x 200 milligram = 1 gram), for 10,000 days (about 27 years), then you have enough in your system to do kidney damage." 
However, the above seem like a wildly optimistic assessment when you consider that between 1% and 5% of all NSAID users are estimated to have a renal event!  Why are these so nasty and hard on the kidneys? After all, isn't limiting inflammation always good? The answer is that NSAIDs produce a very unnatural combination: they simultaneously lower inflammation AND vasodilation. The capillaries in the kidneys are very sensitive to anything that limits their ability to relax and allow more blood flow. NSAIDs sabotage that process.
And I will put a shameless plug in here for plant foods, so many of which have BOTH anti-inflammatories and vasodilators.
CONCLUSIONS: a) The cure can be worse that the disease. b) It is very, very, very difficult to make a synthetic drug that does not cause more problems than it solves.
1) http://www.medscape.com/viewarticle/553966_3, "Natural Antiinflammatory Agents for Pain Relief in Athletes: Lesser-Known Side Effects of NSAIDs"
2) The Journal of Urology, May 2006, 175(5):1812-1816, "Effect of Non steroidal Anti-Inflammatory Drug Use on the incidence of Erectile Dysfunction"
3) Stroke, Submitted on March 29, 2010, Accepted on May 8, 2010, "Increased Risk of Stroke Associated With Nonsteroidal Anti-Inflammatory Drugs. A Nationwide Case Crossover Study"
4) Clinical Gastroenterology, Feb 2000, 14(1):147-159, "How do NSAIDs cause ulcer disease?"