Abuse of prescription and over-the-counter drugs is at an all-time high. More than one in every five teenagers reported using prescription pain killers without a doctor’s permission, and more than one in ten reported using Adderall or Ritalin (stimulants often prescribed for ADD/ADHD) without a doctor’s permission. Abuse is especially common on college campuses. And that shouldn’t be a big surprise, with more than 2,800 prescription drugs on the market and another 2,000 medications available that don’t require a prescription.

With so many prescription drugs illegally “pharmed” on the internet, they’re more available than ever. But these illegitimate prescription drug sites can be shady — the drugs are potentially counterfeit, adulterated, and contaminated. Also, as baby boomers age, the number of prescribed medications has grown overall, increasing availability.

Think about it. All drugs — illicit, prescription, and over-the-counter medicines — change your body chemistry. If they didn’t, you wouldn’t bother taking them. The recommended dosage that you read on the label has been tried and tested to relieve the specific symptoms that are troubling you. If you take more than the recommended dose, there may be all sorts of consequences.

The risks are compounded when it comes to prescription medicines. You may not get your clothes custom-made, but a prescription medication is tailored just for you — doctors calculate (and readjust) doses according to your age, height, and weight, with consideration of your current ailment, past medical history, and other drugs you may be taking.

Dose is only one part of the abuse equation. People also abuse prescription medications by holding on to them for later use, or sharing them with friends. That’s potentially scary. Remember, prescription drugs do not affect all people in the same way, and drug allergies can develop at any stage in life.

What is considered abuse? Abuse occurs whenever a prescription drug or over-the-counter medication is used for anything other than its intended purpose, by someone other than the intended recipient, or in a dosage other than prescribed. Of course, it gets a little tricky because all these medicines can be “misused” or “abused.” The difference lies in the person’s intent — is it being used incorrectly out of ignorance (misuse), or intentionally (abuse)?