That is an excellent question and one that is best answered by your primary care doctor
or another medical care provider. The pills that are sold over the counter have been approved for sale but in most cases, have not been evaluated by the FDA for the claims they make or have been rigorously tested to ensure that they have the correct doses of the drugs they have used or have pharmaceutical grade quality. Aside from that fact, it is important to discuss the concerns you have with your primary care doctor with regards to why you are looking for enhancement pills at this point in your life. Is it that you are having difficulty maintaining or obtaining an erection? If this is the case, then your doctor can prescribe prescription medications that can help with this symptom that are FDA approved and have been shown in clinical trials to be safe and effective. It is also advised that you speak to your doctor as some of the drugs used in the over the counter medications may have adverse effects when used with medications for high blood pressure
such as the medications that you likely take.