Yes, primarily for a few well justified reasons: 1) usage of prescription drugs usually entails significantly greater risks of adverse effects compared to OTC d

Yes, primarily for a few well justified reasons: 1) usage of prescription drugs usually entails significantly greater risks of adverse effects compared to OTC drugs (barring some grandfathered-in legacy substances like acetaminophen, which would probably not be approved for OTC use today), 2) relative to usage of OTC drugs, the stakes associated with usage of an under-performing prescription drug are much greater in magnitude, and 3) there is an economic incentive to produce counterfeit or otherwise subpar prescription drugs that doesn't exist for OTC drugs, the wholesale value of which can be often be measured in fractions of a penny. Counterfeits are also a lot more common in the developing world than people would expect, and this stuff frequently ends up in online pharmacies. Manufacturers of drugs bound for international markets do implement measures that you usually don't see in the US (e.g. consumer-accessible websites/phone lines to verify a lot number and unique serial printed on counterfeit-resistant holograms), but even that doesn't do a lot of good. I've personally purchased antibiotics from a pharmacy in Vietnam that had convincing anti-counterfeit labels - but shame on me for not paying attention to the serial numbers. I bought two boxes with lot numbers and serials that checked out on the manufacturer website...but both boxes had the same serial, which shouldn't have been possible. The hologram stickers were indistinguishable from images of legitimate ones portrayed on the manufacturer website. I'm assuming everything the pharmacy had on hand for that drug (amoxicillin + potassium clavulanate) had the same serial on the label.