I would add that, as in some of his examples, the patients were trying to treat existing (although not necessarily know or diagnosed) medical problems; but with the wrong approach.
I agree with Dr. Rangel that we can safeguard some of our patients from some of the adverse effects of medications and that this is a very important role and a good reason to keep some of these meds from the OTC market.
I would add that a large number of the patients I see misinterpret their symptoms and misdiagnose. In a system where they could get anything OTC, they may use the correct drug for what they think they have, and in safe doses, but the actual disease process might continue unabated and even worsening.
Taking Mevacor because you are "not feeling well" and think your heart needs help may not result in an injury from the Mevacor, but may delay the correct diagnosis. This could result in a more difficult to treat disease or even death.
Update: Don't forget that most commercial insurers won't pay for OTC meds. Don't be fooled when you see support from these companies, it is in their financial interest, not in the interest of what is best for you.