Prozac Ocean: Fish Absorb Our Drugs, and Suffer For It

By Nina Bai | December 2, 2008 2:06 pm

sad fishThe fish are acting funny because they’re on Prozac.

In the U.S., more than 200 million prescriptions for antidepressants are given out every year. A lot of the contents of those pills eventually end up in our water supply, either from patients’ excretions or from pills flushed down the toilet. Since water treatment plants aren’t designed to remove pharmaceuticals, we’re effectively medicating our streams and rivers.

Chemists have found that water downstream of water treatment plants holds a veritable medicine cabinet worth of antidepressants, including venlafaxine, bupropion (Wellbutrin), citalopram (Celexa), fluoxetine (Prozac) and sertraline (Zoloft).

The concentrations of antidepressants in the water—billionths of a gram per liter—aren’t enough to affect larger species, but they are enough to make small fish and fish babies feel woozy. Researcher Meghan McGee tested the effect of antidepressants on young minnows by exposing unhatched and newly-hatched minnows to levels of antidepressants commonly found downstream of water treatment plants. The drugged minnows appeared lethargic and took twice as long to react to stimulus, making them much more vulnerable to predators.

McGee then upped the dosage of antidepressants to see how they would affect fish that feed on minnows, such as hybrid striped bass. When the concentration was increased to several millionths of a gram per liter, the bass spiraled into a drug-induced haze and exhibited some really weird behavior. Some hung around vertically in their tanks, others skimmed the surface with half of their backs exposed in the air (even though they are normally a bottom-dwelling species). They lost their usually voracious appetites and ignored the minnows that swam around them. The males took on feminine characteristics, loosing their masculine facial bumps and growing yolk protein.

In humans, many antidepressants (allegedly) work by altering levels of serotonin in the brain, but some also function like the sex hormone estrogen. It’s not clear how the drugs are working in the fish, but it’s clear all that Prozac isn’t doing them much good. Meanwhile, some communities have begun drug disposal campaigns that collect unused drugs to be incinerated instead of flushed into the water supply.

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DISCOVER: Antidepressants Trigger Suicide Impulses in Teens

Image: flickr / foshie

MORE ABOUT: antidepressants, fish
  • Dan J

    Ok… what is the point in posting this story? NO ONE is going to do anything about this.

  • Vmc

    To be aware.

  • Gary B

    To inform our future piscene overlords how we accidentally created them, and flooded the world to make it safe for them to take over.

  • lauren

    but…. i love da feesh! :(

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  • Nathan

    Story says levels too low to affect us, but this is just one category of lots of drugs we’re finding in the water. There could easily be a cumulative effect up the food chain some day. I read about a new machine that finds drugs in the water in real time. Saw it at but I don’t know if it’s legit. If it is, however, we could know what’s floating our way always, not just after delayed lab tests. Or after we see the nasty effects. Think these fish are happy?

  • Will

    Do the chemists realize it can take 4-6 weeks for the antidepressants to take effect?

  • DuhWill

    Will, 4 to 6 weeks is the time it takes for those meds to begin to work in full grown human beings, with warm blooded metabolisms and different biochemistry. In smaller creatures the effects could be seen much faster.

  • Uncle B

    I take huge amounts of ant-depressants and, for me they are a God-send! I also have a large veggie garden out back, and feed myself and my wife from it! Very green! I also recycle my urine in sawdust, compost it, and fertilize my garden with it! Yuuuuk! by American standards, but the (GRD) great republican depression is about to change all that! Look in Google. Around all the large Asian cities you will find a “Green Zone”. This is where they recycle their urine and solids too! They apparently don’t compost it first either! YuuuuK twice! Will the Anti-depressants affect my veggies? Will I have happy moles? Will I break out in great scabs and die a terrible unpreventable death? I doubt it! My worry is that the run-off from my gardening adventure will hurt fish in nearby rivers and lakes!

  • FDR

    You made ants depressed? wtf..

  • julez

    Awesome! Every time I get depressed now, I’ll just go to my nearest sushi restaurant.

  • SRS

    Oh no! more bad news about polluting.

  • Heather

    I have a problem with incineration as well, that’s not the proper solution. Whatever chemicals went into the drugs are going to be released into the air. (We’ll all be inhaling procac, mmmm.) If we want to stop the harmful residue from infecting wildlife and even ourselves, the problem must be targeted in production. There should be some way to develop some sort of recycling process developed.

  • Oh wow

    I completly lost my respect for psychiatrists and whiners who won’t back off until they get their antidepressants prescribed.

  • scienceroom

    It’s terrible.
    It’s time to save my ocean.

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  • anon


    i dont mean to sound pessimistic, but… sorry its a little late, things are beyond our control at this point and there is no hope to ‘fix’ what we broke.

  • In Healthcare

    So that’s why they say fish are good for depression…..

    On a more serious note, are you saying we should put the needs of minnows above the needs of our patients? I realize antidepressants are over prescribed, but many patients have a real illness and suffer greatly from it. Sometimes antidepressants are prescribed to help with other illnesses that aren’t even psychiatric in nature at all. Sure, maybe we should be better at filtering our water, maybe we should have some other way of disposing of meds other than flushing them. Personally, I drink filtered water. But please, don’t deprive people of meds they need because fish are “suffering”.

  • jimmy

    the earth is totally screwed…hooray humans!

  • Kelly

    Most people who need anti-depressants need them the same way diabetics need insulin. I have never understood why the same people who would never dream of making fun of a diabetic or denigrate the doctors for prescribing their medication would do these same things to a person diagnosed with depression. Besides showing a complete lack of empathy and class, it also shows how incredibly ignorant some people are about depression. I feel bad about what the anti-depressants are doing to our water too, but not so bad that I want to go back to the days of constantly having to find reasons to live and not commit suicide. If that’s whining to get my meds, then I’ll gladly whine for them.

  • messenger

    typical American way of getting rid of stuff you didn’t need in the first place… dump it in the toilet… dump it in the dustbin… just get it out of the house, it magically disappears, right?

    Problem is it eventually will come back and bite you in the bottom, unfortunately with the rest of the world…

    Sympathies to people who really need antidepressants… but 200 million prescriptions per year? You people went totally over the edge… Get a grip on yourselves… Most of you have no idea what depression really is, but when your pet dog dies you act as if it was the end of the world…

  • messenger

    To “In Healthcare”:
    you say ” maybe we should have some other way of disposing of meds other than flushing them”

    Is this a joke??? We do have a better way:
    – don’t get them in the first place
    – if you really need them and they expire bring them back to your pharmacy…

  • http://none Mike

    For me the best anti-depressant is to watch comedy on TV, pills just make you more depressed.

  • Eli Gundry

    My question is: What do these drug collection drives do with them?

  • wow

    ok, so if you multiply the dosage by thousands of times your lab fish start acting weird? NO SHIT, try increasing the natural levels of iron or iodine or thousands of other naturally occuring substances in water. Many will produce behavioral side effecs and several even become lethal/ Now that’s not to say prozac in the water is natural, or good, but aren’t there more pressing issues? personally, i’m slightly more concerned for the highly endangered polar bear who is losing miles of habitat as we speak.

  • jasen

    The fish are acting funny because they’re on Prozac Ocean!! thumbs up!!

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  • Prozac Saves Lives

    All the Prozac naysayers are probably people who have never lost a loved one to a murder or suicide, therefore never having a need for such medication. I can tell you from personal life experiences that I never needed anything either until life dealt me a major blow by losing many family members in one year.
    I’m also an avid planet lover & certainly do not want to see any other species on our planet suffer. I’m sorry for the fish, for any animal or human who suffers, but we all know that not everyone gives a rats rear either. I’m doing the best I can with what life has dealt. If it’s either me or the fish, I’ll have to go with me, as a human at the top of the food chain.

  • aidan

    its not too late to fix what are broken..poor fishes their suffering because of us! :(

  • carl

    at least the fish are not guna suffer from depression

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  • Darth Continent

    Sweet, so we’re laying the foundation for a bunch of disgruntled fish to nibble us to death, then get themselves eaten by a convenient shark!


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