All drugs are regulated by the FDA, even if a drug patent is expired you need to get FDA approval to sell a generic version, which would cost millions. The only way around this, is if you market your product as not for human consumption or make some obscure research drug and market it as a health supplement.

Of course the latter two eventually will get you in deep shit with the FDA.

But could you make it for yourself?

...or at least meet the legal definition of making it oneself? Like the "build your own AR-15" kits where 99% of the work is already done, but for insulin?

You can produce the drugs but very hard to get anyone to buy it, as your product is not recognized by pharmacies and insurance companies as legitimate. Drugs doesn't get bought in the US unless it is carried by pharmacies and pharmacies won't carry your prescription drug unless insurance covers it.

So it sounds that the solution to the problem is to establish an online pharmacy chain and make sure that you gain a good reputation?

I'm sure Amazon will manage to sell you counterfeit insulin.

All I'm thinking is that there's likely some very desperate people out there looking very hard for these drugs in a cheaper form, and with a bit of viral marketing magic from the pharmacist I don't think it would be a massive stretch to match the two.

It wouldn't be hard except for FDA regulations around manufacturing/selling drugs intended for human use.

Ah, so we should just get rid of those regulations and let the little guy compete!

Not so fast. Maybe the first new market entrants are motivated by altruism as much as by profit. They do everything carefully but charge prices closer to cost. Patients pay less and there are hardly any downsides, except to the financials of legacy pharma companies.

But by year 3 there are people who have learned that you can buy barrels of technical-grade active pharmaceutical ingredients off of Alibaba and make pills from them without any quality control in between. Sometimes the products are contaminated with carcinogens. Sometimes they vary widely in potency across lot numbers. In the absence of regulations, fraudulent and shoddy products become widespread. It would be like the supplements industry, except that people actually die if they don't take real prescription drugs they need (this is less common for people who are sold fake herbs.)

I assume you can't just manufacturer unpatented drugs and sell them as drugs.

You likely need to prove that you are producing a clean product, etc.

Similar to how there is regulation of you make food at industrial scale.

I don't believe so. There are foreign online pharmacies of various reliability that a good number of people use. Folks near the border go up to Canada as well. None of that is legal, but it's not enforced. I imagine the outcry would be too great.