Sometimes parents are the last to know.
Studies show that the average parents whose kids are using drugs don't know about it for six months.
That's a long time.
More than enough for kids and young adults to develop a prescription drug addiction or do other serious damage.
In fact, the news is full of stories about kids who died from prescription drug overdoses.
And sometimes their parents didn't even know they were taking them.
But there are warning signs, and every parent should know them cold.
How can you tell if your kids are popping pills? Grades dropping.
It might happen right away or it might take a little while.
Unfortunately, this isn't something you can find out every week; you have to wait for exams.
So you also need to keep a very close eye on school performance, interest and participation.
Changes in mood or behavior of any sort.
These changes could even be for the better.
If your kid tends to be sullen or resistive, for example, and all of a sudden is getting much easier to get along with, don't just think they've changed for no reason.
It could be that they're propping themselves up with drugs.
On the other hand, the changes they go through could be negative - sleeping longer, staying out later, becoming moody.
Being more secretive about where they're going, what they're doing, and who they're with.
Making new friends and not seeing their old friends as frequently or at all.
Often they've met kids who take drugs and are now taking them as well.
They'll gravitate to those new friends.
Any physical symptoms.
There are literally hundreds of side effects from prescription drugs.
You need to be familiar with all of them and how to recognize them.
There seems to be fewer pills in your own medicine bottles.
Experts advise that if you have the kind of medication others could use to get high, keep them locked up.
These include OxyContin and other painkillers, all tranquilizers and sedatives, anti-anxiety drugs, sleeping pills, antidepressants or antipsychotics.
If you don't know what category your drugs fall into you'd better find out.
Doctors often prescribe drugs for a condition other than which they were intended.
Don't assume that because you're taking medicine for arthritis, for example, that your drugs are of no interest to someone without it.
Most parents think of prescription drugs as medicine.
It never occurs to them that someone who doesn't have the condition they're being treated for they would want them or even get anything out of them.
Parents, along with their young adult children, also think that because the drugs came from a doctor, they're safe.
Those days are over.
The drugs we take are dangerous and we live in a drug culture; people take prescription drugs freely for every problem they run into - physical or emotional.
And even if that doesn't describe your household, it will describe the household of others your kids contact.
And some of those kids - whether they're 13 years old or in college - will be taking them and will suggest your kids do the same.
Educate yourself, educate your kids, and know the warning signs of prescription drub abuse.