Safely Dispose of Leftover Pills and Keep Drugs out of Drinking Water

leftover pills

When your doctor prescribes medication for you, you may have pills left over.  Properly disposing of unused medications has become more challenging in a country where there are so many prescription medications.  The traditional advice was to flush leftover medicines down the toilet, especially drugs that could be abused or harmful, such as OxyContin, Percocet, and morphine—but that means they end up in our drinking water.[1]   An investigation by the Associated Press in 2008 found that municipal water supplies in several areas were contaminated with antibiotics, hormones from birth control pills and other medications, seizure medications, blood pressure medications, and antidepressants.[2]

Flushing unused medicine down the toilet isn’t the only way that drugs get into our water supply. Medicines get into our water when people take them and then excrete them in their urine.  Excretions of drugs that have been ingested and metabolized are somewhat less of a concern. However, conventional water treatment practices are not able to fully remove these metabolized drugs before they reach our drinking water. When some drugs enter the water supply, they are there to stay.[3]

Another way medicine gets into the water is when people wash off ointments and creams.  But what comes out of our bodies and off our skin is very diluted. When we flush medicines down the toilet we introduce drugs into the water supply in their full concentration.

How Can Drugs in the Water Affect Our Health?

The good news is that the amounts of drugs currently detected in drinking water are probably too small to have a short-term effect on human health.[4]  But, nobody knows what the effects on humans are of long-term daily exposure to drugs at these levels. We know, for instance, that chemicals in our drinking water that act like hormones actually do more harm to our health at low doses than at high doses![5]  These chemicals (endocrine disrupting compounds or EDCs) are used mainly in plastics, shampoos, and lotions.

Much of what we know about regular exposure to low doses of drugs comes from studying fish and other animals because the same drugs found in drinking water have also been found in ground water and in wetlands, lakes, and streams. For instance, a study published in the Journal of Environmental Science and Technology in 2011 found that drugs in the water can accumulate in the brains of fish and cause changes in behavior.[6]  We have much to learn about the long-term effects on fish and other animals (some of which we eat) as well as on the environment.

If drugs in our waterways are affecting fish, could drugs in drinking water affect our children? Young children drink more water for their size than adults, so the amount of drugs they are ingesting by drinking water is much larger, pound for pound.[7]

Are There Really that Many Unused Drugs Out There?

According the Centers for Disease Control and Prevention (CDC), 48% of Americans surveyed in 2008 reported using at least one prescription drug in the past month.[8]  This means that about 150 million Americans use prescription drugs at any given time.  This could translate to hundreds of thousands if not millions of pounds of unused drugs per year.  A recent drug take-back initiative organized by the Drug Enforcement Administration (DEA) reported collecting over 2 million pounds of drugs in 2 years.[9]

Can I Toss Them in the Garbage?

The FDA recommends disposing of most unused drugs in the garbage by removing them from their original containers and mixing them with undesirable substances like coffee grounds or cat litter.[1]  This makes the medication less recognizable to someone searching for potentially dangerous drugs like painkillers in the garbage.  The FDA also suggests that you put the drugs and coffee ground mixture into a sealable bag to prevent the medication from leaking.  While this is better than flushing pills down the toilet, the drugs can still leech into the groundwater.  For example, the bag or container can get punctured on the way to the landfill and the drugs can leech into aquifers below the landfill.

What is the Best Way to Dispose of My Medications?

Drug take-back programs are a great way for you to safely dispose of your unused medications.  They are often sponsored by hospitals, the Drug Enforcement Administration (DEA), or your community.  The DEA holds a National Drug Take-Back Initiative once a year in over 5,000 locations, so be on the lookout for this and check here on the DEA website to find drop-off locations in your area.   Many police stations also host drug take-back events or have drop-off boxes where you can leave your unused medications.  Most pharmacies will take back your medications for a small fee.

The drugs that are collected using take-back programs are usually sent to pharmaceutical companies to be incinerated.  Some research shows that incineration can produce toxic chemicals called dioxins that can be released into the air.  The leftover ash is put into regular landfills so it is possible that it can leech into the soil and groundwater.[10]  However, compared to other drug disposal methods, take-back programs are still the safest way to dispose of your unused drugs.

What Else Can I Do to Keep Medicines Out of the Water Supply?

Why do we even have leftover pills? Healthcare professionals are usually required to fill prescriptions in certain units, regardless of whether or not you need to finish taking all of the medicine in the prescription.[11]

Some prescription drugs—pain killers, for instance—are taken on an as-needed basis so you can end up with a lot of leftover pills.  Doctors and pharmacies should develop strategies to reduce the amounts of unused drugs.  Meanwhile, you can do your part by talking to your doctor about how many pills you expect to need and properly disposing of your leftover pills.

If you are buying over-the-counter medications, don’t purchase more medicine than you can use before the expiration date.  This will save you from wasting money and save you from having expired medicine in your house.

 All articles on our website are reviewed and approved by Dr. Diana Zuckerman and other senior staff. 


1.    “How to Dispose of Unused Medicines.” US Food and Drug Administration. FDA, n.d. Web. 23 Apr. 2013.

2.    Donn, J; Mendoza, M; and Pritchard, J; AP: Drugs found in drinking water, USA Today. March 10, 2008. Retrieved from:

3.    “Fighting Drugs In Drinking Water.” Fighting Drugs In Drinking Water | Clean Water Action. Clean Water Action, n.d. Web. 29 May 2013. <>.

4.    Kumar, A and Xagagoraraki, I, Human Health Risk Assessment of Pharmaceuticals in Water: An Uncertainty Analysis of Metprobabmate, Carbamazepine, and Phenytion. Regulatory Toxicology and Pharmacology. 57(1) pp.146-56.

5.    Vandenberg LN, Colborn T, Hayes TB, et al. “Hormones and Endocrine-disrupting Chemicals: Low-Dose Effects and Nonmonotonic Dose Responses.” Endocrine Reviews. March 2012. Web.16 Apr. 2012.

6.    Belluck, Pam. “Traces of Anxiety Drug May Affect Behavior in Fish.” The New York Times. NY Times, 14 Feb. 2013. Web. 23 Apr. 2013. <>. 

7.     Bearer, CF. Environmental health hazards: How children are different from adults. The Future of Children. 5(2)pp.11-26, 1995.

8.    “Therapeutic Drug Use.” Centers for Disease Control and Prevention. CDC, 18 Feb. 2012. Web. 23 Apr. 2013. <>.

9.    “Drug Disposal – National Take-Back Initiative.” US Department of Justice Drug Enforcement Administration. DEA, Oct. 2012. Web. 23 Apr. 2013. <>.

10.  Singh, S and Prakash, V, Toxic environmental releases from medical waste incineration: A review. Environmental Monitoring and Assessment. 132 pp. 167-81. 2006.

11.  “Prescription Drug Abuse.” Office of National Drug Control Policy. The White House, n.d. Web. 24 Apr. 2013.