Pravastatin is the generic name for Pravachol, one of the earliest statins used to lower LDL cholesterol levels. Since it is one of the most mild statins in terms of efficacy, its side effect profile is typically the most benign of the entire class. Nonetheless, there are still several side effects of this drug that one needs to look out for.
All statins, including pravastatin, have the potential to cause liver damage. In clinical trials it was found to raise liver enzyme levels in a small percentage of users. For this reason, no one should take it without having regular liver enzyme monitoring done in order to ensure that there is no substantial damage to the liver.
Rhabdomyolysis with acute renal failure is also one of the rarely observed side effects, as with most statins. This refers to a rapid break down of muscle tissue, which causes myoglobin to accumulate in the bloodstream. Long term levels of this breakdown product can damage the kidney, leading to rare cases of kidney disease. Note that many people who take statins commonly complain on muscle pain for this reason and will often switch medicines before any significant permanent damage is done.
The profile of pravastatin side effects is pretty benign as prescription medicines go, particularly in the statin class. That being said, one must always remember that these are man-made molecules and the long term side-effect of decades of habitual use might not be well known for a while since rigorous clinical trial follow-up is usually limited to a few years before a drug is approved.