If you're like many people, you probably have a few old prescriptions that have been hanging around for years. Those orange plastic bottles might contain the last antibiotic from a bout of strep throat or a medication that you never even used. There's a simple way to get rid of all your old medicines in a responsible way.

You might not think that your old prescriptions can affect the planet in a big way. However, when you start to add up the ones that you contribute, the ones your neighbors do, the ones in other countries and around the world — you can start to see how they quickly add up.

The annual Prescription Drug Take Back Day held by the Drug Enforcement Administration (DEA) takes place Saturday from 10 a.m. to 2 p.m. At multiple locations, you will be able to drop off your old medications.

The DEA makes it easy to find those drop-off locations. Go to www.startribune.com/a2201, click on "Locate Collection Site Near You" and type in your ZIP code. Many outstate sites are listed there, along with three in the metro area: the Washington County Sheriff's Office (14949 N. 62nd St., Stillwater), Coon Rapids Police Department (11155 Robinson Dr. NW.) and Carver County Sheriff's Office (316 Broadway Av., Carver).

Hennepin and Ramsey Counties have ongoing drug drop-off programs, Mondays through Fridays in Ramsey and most days in Hennepin.

The Ramsey County locations (651-633-3279) are:

• 425 Grove St., St. Paul.

• 1411 Paul Kirkwold Dr., Arden Hills.

The Hennepin County sites (612-348-3744) are:

• 6125 Shingle Creek Pkwy., Brooklyn Center.

• 9401 83rd Av. N., Brooklyn Park.

• 7009 York Av. S., Edina.

• 401 4th Av. S., Minneapolis.

• 12601 Ridgedale Dr., ­Minnetonka.

• 4141 Shoreline Dr., Spring Park.

There are many advantages to going through your bathroom and kitchen cabinets to seek out these unused medications and drop them off on Saturday. The DEA points out that unused prescriptions are often stolen, misused or the cause of accidental poisonings and overdoses at home. These drugs also can damage ecosystems if disposed of incorrectly.

If the national Take Back Day or regular drop-off locations aren't convenient for you, there are other options. You can now buy a postage-paid envelope to dispose of many prescriptions and over-the-counter drugs responsibly. The Take Away Environmental Return System (www.sharpsinc.com/locations) is now available through many national retailers — especially pharmacies and online.

Staff Writer Bill Ward contributed to this article.