Insurance companies are changing the game so people understand and appreciate just how expensive the newest prescription drugs can be. The new "Tier 4" pricing will change from a fixed co-pay amount to a percentage of the total cost, so instead of the small co-pay of $10 or $20 patients are now paying, they'll pay a percentage of the price of the drug. As an example if your drug is actually $500 per bottle, say $16.67 per pill for a month, then instead of just a few dollars you might pay $150 or 30% of the total. If you have one of the really expensive new drugs, say $1,500 per bottle or $50 per pill, you might spend $450 for each refill ... or $5,400 per year for the medication.
Obviously the insurance companies want you to appreciate the cost difference between old generic drugs with proven effectiveness to the latest, as-seen-on-TV drugs which can be incredibly expensive. As gamblers say, if you have "more skin in the game" then you'll decide what it's really worth.
The good news is by making prescription drugs more expensive the insurance companies are also going to increase the popularity of complementary and alternative medicine. After all, if it's your money you may as well spend it on what you want.