Prescription drugs cost patients plenty, but the most expensive among them can be as much per year as a car (an average of $30,000 a year for older adults using brand name prescription drugs according to AARP). In some cases, health insurance won't even help with the cost. Single-payer health care in other countries puts a greater burden on U.S. consumers and insurers, and research and development costs help drive up drug prices. But so does a lack of competition, generic or otherwise, and advertising expenses of more than $5 billion a year, which is why you should never let glossy ads guide your medication. With help from GoodRx, we found 18 drugs that cost patients as much as they'd pay for cars, trucks or SUVs outright.