Chantix Linked to Violence and Aggressive Behavior in New Study

The findings of a new study seem to confirm the link between side effects of Chantix and violent behavior. Pfizer’s blockbuster smoking cessation drug has previously been linked to an increased risk of suicide and other psychiatric side effects, but this is the first to specifically examine reports of violence and aggression.

Researchers from the Institute for Safe Medication Practices published a report in the current issue of the medical journal The Annals of Pharmacotherapy, providing evidence that the use of Chantix is linked to aggressive and violent behavior, which could result in a serious injury for the user or those around them.

Chantix (varenicline) was approved in the United States by the FDA in 2006 as a prescription medication to help people quit smoking. The drug works by reducing the positive feelings that come from cigarettes, blocking the receptors in the brain commonly stimulated by nicotine. However, the impact of the drug on the brain has resulted in a number of reports from users who experienced sudden, unusually aggressive behavior, thoughts of self-harm and suicide.

In June 2009, a “black box” warning was added to the medication about the potential risk of problems with Chantix, indicating that some users have experienced changes in behavior, depression and suicidal thoughts. Pfizer has also been required to conduct clinical trials providing more data on how often neuropsychiatric symptoms and suicide with Chantix occur and what conditions cause them.

The new study looked specifically at violent or aggressive acts or behaviors, which were not included as part of the prior warnings. Researchers studied 78 Chantix adverse event reports submitted to FDA through its MedWatch database, as well as seven other cases from other sources. They said they found several common characteristics among cases where Chantix appeared to be linked to violence or aggression.

Scientists found that the acts of violence were inexplicable and unprovoked, the Chantix users victimized anyone nearby, there was no prior indication of similar behavior and the psychiatric side effects occurred quickly; often before they had gotten to the point in their Chantix use where they had stopped smoking. Researchers found that violent and aggressive behavior ended for 93% of the subjects when they stopped taking Chantix.

In one case examined by the researchers, a 47-year-old woman who had taken Chantix for a month started assaulting her daughters and yelling at them before committing suicide by shooting herself. In another case, a man who had been taking Chantix for eight days choked his wife in a fit of rage and then hung himself. Less extreme cases include people who suddenly woke up and assaulted the person closest to them, started fights and destroyed property, often their own.

The researchers said that while there has been plenty of attention paid to Chantix suicide problems, more attention needs to be brought to the violence and aggression side effects of Chantix as well. They recommended that doctors do more to warn patients about the risk of Chantix violent behavior and that patients immediately report any strange and uncharacteristic violent urges while taking the drug.

Lawsuits over Chantix have been filed in state and federal courts throughout the United States on behalf of individuals who have suffered injuries from the neuropsychiatric side effects of Chantix, skin reactions from Chantix and for family members of individuals who have committed suicide on Chantix.

In October 2009, the U.S. Judicial Panel on Multidistrict Litigation consolidated all federal Chantix lawsuits in the U.S. District Court for the Northern District of Alabama. According to a pretrial scheduling order issued earlier this year, the first Chantix trial is unlikely to reach a jury until at least 2012.

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  1. Kayla Reply

    I took Chantix for approximately two weeks and finally quit immediately when I found myself being verbally abusive and mean to my coworkers. My spouse had been telling me that I acted like the devil….of course I did not really put much thought into his accusations until I kept hearing from friends and family that Chantix was making me very mean, impatient, and violent.

  2. Matt Reply

    I took Chantix for about a month. It made me feel pretty strange while I was taking it, but it got me off of cigarettes. After smoking for over 20 years I have been smoke free for 1.5 years. Chantix is not without it’s risks but it is incredibly effective.

  3. Jesse Reply

    i have been taking chantix for 28 days…in other word i just made it through the “box set” and am supposed to begin my second perscription today….NOT A CHANCE…..I have been abusing chewing tobacco for 17 years now will quit… but not like this. I woke up last night choking…when i finally got my breath back…i got cold sweats and numbeness for awhile…its hard to keep track of time….either way i called my doctor and his advice is to quit… right now. I will admit that i have no desire for nicotine but we’ll see what happens when Chantix is out of my system. Man what wierd and potent little drug this is….

  4. Lisa Reply

    I took Chantix for 2 months and YES it is a very bad drug. The doctor new that I had a history with depression and I was fine untill I started taking Chantix. The drug changed my behavior also and I took this drug before the warnings came out. If I knew about the risk I would of went with the patch instead. Also I paid 150.00 for chantix. So I’m depressed again and have been for a long long time. Do NOT take this drug if you have had problems with dpression it will come back! They should give me free meds for my depression and give me a refund on what I spent for chantix!

  5. Marian Reply

    I took chantix for about 2 months. It was incredible that stop me from
    smoking and cravings. I think it works great. I actually never experience
    any side effects of weird behavior, instead, it made me relax and have
    very intense dreams. The only side effect was nausea that last till today.
    People have to understand that meds have side effects and sometimes
    that is the price to quit what is killing us. Nothing ever works better than chantix. That is the truth.

  6. Dy Reply

    My husband started the Chantix about a month or so ago and he was going excellent on it, but i did notice here and there in the beginning he was somewhat edgy, I put it off that yes he is trying to quit smoking and he would be edgy..My husband has never tried to hurt me in any way i am dealing with cancer among many many other health issues i am a very sick lady,but he has ALWAYS been supportive and kind.But a couple of weeks ago we had a minor disagreement over the dish washer (silly i know) and we NEVER fight about small petty things, all of a sudden he lashed out at me with verbal abuse told me to get out of the house and was cussing at me horribly. Later on after he settled down after throwing things (which he NEVER DOES..been with him 12 yrs) i was able to calm him down and he just broke down on the way he treated me…I noticed a HUGE change in him about 3 weeks into it. I guess you would say he was getting ready to start the 2nd box when this happend. Have any women out there had problems with their husbands lashing out that normally dont? He is getting better now hes off of it (almost 2 weeks) but how long will this linger in his system? i am really trying to walk on eggshells to keep the peace and ALL I WANT HIS MY HUSBAND BACK!

  7. Shana Reply

    I am on the second box, and today I hit my 13 year old child. I punched him as hard as I could three times, because he wasn’t cleaning his room. I cannot even believe I would yell, scream, and punch my son. It was a wonderful day of church, a beautiful Easter dinner, and playing outside, and then this. The anger, and now the sadness I feel, has been overwhelming. I just bought a pack of cigarettes and didn’t take my pill tonight….

  8. ShanaM Reply

    Shocked…I am on the second box, and today I hit my 13 year old child. I punched him as hard as I could three times, because he wasn’t cleaning his room. I cannot even believe I would yell, scream, and punch my son. It was a wonderful day of church, a beautiful Easter dinner, and playing outside, and then this. The anger, and now the sadness I feel, has been overwhelming. I just bought a pack of cigarettes and didn’t take my pill tonight….

  9. Katleen Reply

    I just ended my first 2 weeks with Chantix. I’ve been smoking for 40 years, at least a pack a day. I also take Cymbalta for depression. I know It’s supposed to build up in your system, but it did not do anything for me in 2 weeks but make me more depressed, anxious, irritable, sleepless at night, sleepy durring the day, shaky with heart palpitations, at one point I felt like I was having a heart attack! So, I stopped taking the Chantix and its going to take more than 2 weeks to leave my system. I smoked while taking the Chantix, eventhough, I did cut down a lot, I made a pack last a whole week. But, with the side effects I had and what I’ve been reading especially about people with depression taking Chantix, I don’t want to end my life or hurt anyone, I just want to stop smoking! I want a refund of the $160.00 out of pocket thst I spent on the prescription!

  10. N. McDaniel Reply

    My (ex) fpgirlfriend was a lifelong smoker and began taking Chantrix as a last resort. She changed bhaviorally. At first it was just verbal abuse. It increased her aggression to the point that when she renewed her perscripton, she date raped me. It made her a completely different person. As acresult, I am a male survivor of sexual abuse.

    Be very careful with this drug. It is effective and yes, can help. She is a nonsmoker now for a year. I am left paying the price for her liberation from smoking for the rest of my life I must live with the Hell of Post Traumatuc Stress Disorder (in my opinion,not worth it). Weigh the costs and benefits and be careful.

  11. Kelly Reply

    My boyfriend tried taking this pill for almost 27 days and turned him into a complete monster he was having fits of violent anger ,keep in mind normally he would not hurt a fly ,even the smallest thing would push him over the deep end even to where he picked me up and threw me ,even grabbing my daughters boyfriend by the throat ,these pills are bad and I wouldn’t suggest anyone taking them yes he quit smoking from them but he’s still not the same he stopped taking them almost a week ago and he’s still not the person I remember if you plan on quitting try to find another way to do it these pills are scary u never know what kind of monster you might turn into he even would say “wish I was dead ” I do not recommend these pills at all I’m not even sure why they still give them to people it’s not worth it just to quit smoking it was a real life nightmare wonder how much worse things could have gotten if he kept taking them if u are on them stop immediately !

  12. Lani Reply

    My husband and I have our fair share of arguments; however, since he started taking Chantix 3 weeks ago, he has become significantly more aggressive. Even mild disagreements cause him to interrupt, scream, put me down, threaten divorce, and remember things differently than how they actually happened (in a way that justifies his anger). He seems incapable of coming to peaceful resolution on issues that become heated. Even after hours or days of cooling down and (what should be) processing the issue, he’ll go right back into a rage state if the topic is revisited. He’s also been violent and fitful in his sleep – tossing, turning, yelling out, and he even kicked me hard with both feet. As much as I want him to be a healthy non-smoker, I’ve endured so much abuse at this point that I think I’d rather he just remained a smoker instead. I asked him tonight to stop taking it, but he doesn’t even realize how much it is affecting him. I’m scared this may cost us our marriage.

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