If you have a need for a prescription with costs in that range, the prescription itself is likely a minimal cost in the whole scheme of healthcare costs you have.
Specialists usually charge significantly more than primary care physicians and an unforseen trip to the ER can easily cost $20k. It's not as simple as working an extra month or two.
The risks of not having insurance are utterly terrible financial handcuffs. I'm just starting down the path of cancer treatments, the coverages (or lack thereof) and costs are eye-opening, and scary.