Alongside physical side effects such as dry mouth and insomnia, phentermine also causes more psychological side effects, such as depression, anxiety and anger. In fact, increased anger on phentermine even has its own term, as this side effect is commonly known as ‘phen rage’. If you’re wondering why you’re feeling angry on phentermine or how to deal with this side effect then read on. Here we explain what causes this anger and share some tips on what to do if you’re experiencing phen rage.

What Is Phen Rage?

‘Phen rage’ is the name given to the side effect of increased anger as a result of taking phentermine. Phen rage encompasses feelings of frustration, impatience, hostility, irritability, and anger. This anger is often directed outwards in angry outbursts, shouting, and even physical destruction or violence. So, if you’ve noticed that you’re suddenly overreacting to situations which would not usually have caused this effect then it’s likely that you’re experiencing phen rage. But you’re certainly not alone; phen rage is a reasonably common side effect, as shown here in our poll of phentermine forum users. It can be seen that around 22% of respondents reported that they had experienced this effect. In addition, our phentermine forum contains many conversations between phentermine users sharing accounts of feeling angry as a result of taking phentermine.

Why Am I Angry On Phentermine?

It is thought that there are three main reasons why phentermine causes users to become unusually angry:

Phentermine Stimulates Your ‘Fight’ Response

Phentermine causes the brain to stimulate the adrenal glands to release neurotransmitters which signal a fight-or-flight response. This is similar to the reaction of our bodies when we are faced with dangerous or exhilarating situations. On the plus side, this leads to appetite suppression as hunger becomes a lesser priority, and energy is released to help you to either run away or stay and fight. However, the stimulation of adrenaline and norepinephrine that phentermine causes also mimics the reaction your body has when you’re angry. This leads you to an altered state of consciousness, helping you get ready to ‘fight’ when perceived problems occur. You may even stop thinking clearly, leading to irrational behavior and extreme reactions that you might not recall once the anger subsides.

Phentermine Amplifies Emotional Reactions

As a stimulant, phentermine stimulates your metabolism and energy levels, but that it also tends to stimulate and magnify your feelings too. This means that your normal reactions to situations become amplified, causing extreme emotional reactions. This explains why some people report positive emotional reactions to phentermine, such as feeling ‘high’ and happy, while others experience negative reactions such as depression, or extreme anger.

Phentermine Causes Hormonal Fluctuations

It is thought that anger on phentermine is due to the way that the dramatic weight loss often experienced on phentermine can effect hormones. Dramatic weight loss causes fluctuations in hormone levels as the release of estrogen is partially based on the amount of fat cells in the body. Hormonal fluctuations can then result in mood swings and irritability in the same way that some women experience while suffering from pre-menstrual syndrome (PMS) pregnancy, perimenopause and/or menopause.


How To Cope With Phen Rage

Side effects fueled by hormonal changes are hard to control, so overcoming phen rage is not easy. However, there are actions you can take to help you feel less angry on phentermine, and ways to ensure that phen rage doesn’t cause too much damage to you and your relationships.

1. Prioritize Sleep

A lack of sleep leaves us tense, irritable and prone to anger, so insomnia on phentermine in combination with hormonal fluctuations makes angry reactions all the more understandable. Follow this advice to combat insomnia, and be sure to talk to your doctor if insomnia persists, as he or she may advise a reduction in your dosage to minimize side effects.

2. Take A Timeout

Timeouts aren’t just for kids; give yourself short breaks during more stressful times of the day. A few moments of quiet time might help to prepare you for what’s ahead without getting angry.

3. Seek Support

You family, friends and colleagues are likely to bear the brunt of your anger, so it’s a good idea to tell them how phentermine is affecting you. It’s important to explain how the things you may have said and done recently aren’t how you really feel. Most forum posts regarding phen rage show how many users are unwilling to discuss how phentermine is making them angry. But it’s better that your loved ones know that phentermine is the cause for your recent angry outbursts, rather than letting them worry about what could be wrong. If you’ve decided not to tell anyone about taking phentermine then our forum is a great way to connect to others on phentermine.

4. Get Active

Exercise is a great stress-reliever, plus getting active helps you to release those hormones urging you to ‘fight’ and direct them into something more productive than an argument with your partner. And, the rush of endorphins that heart-pumping exercise gives you will help you to feel a million times better afterwards. Or, if you feel your anger escalating and you’re nowhere near the gym, go for a brisk walk or direct your anger into a physical task such as cleaning. This way you can take your frustrations out on your kitchen rather than your kids.

5. Avoid Alcohol

Alcohol should definitely be avoided by those experiencing anger on phentermine. Alcohol can cause an increase in anger and a decrease in rational thinking, meaning that losing your temper is even more likely after drinking.

6. Identify Triggers

Although phen rage can strike as a result of seemingly trivial situations, identifying why these result in angry outbursts can help to avoid these occurring in the future. It could be small things that used to annoy you a little, but which then become triggers for phen rage due to hormonal fluctuations. So, if it bugs you when your partner leaves dishes in the sink, or when your colleague puts the air-con on full blast without asking you, choose a calm moment to tell them that you’d appreciate it if they didn’t do that. Often we let these minor annoyances slide because we find it easier to avoid confrontation. But, it’s better to voice your preferences than let this frustration build up into an angry outburst.

7. Eat Nutritiously

An overlooked cause of anger is your diet. The term ‘hangry’ refers to the combination of anger and hunger, where your body lacks nutrients and your mood shifts to hunger-fueled anger. To avoid this you should eat regular nutritious meals full of a wide range of nutrients. Also be sure to eat mood-boosting healthy foods to help balance out your hormones. If you’ve reacted angrily on phentermine after skipping a meal then you know that hunger affects your anger response. Avoid this by packing snacks and planning meals ahead.

The good news is that, like other side effects of phentermine, phen rage does subside over time. But, if you feel that your anger is hard to control, or is ruining relationships, then you should ask your doctor for help.

Do you find yourself getting angry on phentermine? Let us know your phen rage experiences by commenting below.


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10 Responses

  1. I thought it was just me, I feel angry and sad and I didn’t know why but now it makes sense. I have been horrible to my kids this week too, I feel so bad after but in the moment, I just lose it

    • Me too!!! Exactly. I’m stopping this medication. Its not worth it.

    • Same here :, (

  2. Me too, my husband says I have been such a B since starting phentermine. I know I am being unreasonable and overdramatic but it’s like someone else takes over.

  3. OH MY GOSH!!! I truly thought it was post menopausal!!! I never went on hormones. This could definitely be a combination of both!!

  4. Just read that Trump may be taking this drug, although he won’t release his medical records. Could explain a lot.

    • Too funny Toni!!!

  5. I feel like a raving lunatic. Can’t handle the stupidest little glitches like my vacuum clogging up. Had a major meltdown. I’m on going to take for a month. It’s been a week. Lost 7 pounds so that’s good but it’s really making me crazy!!

  6. I can definitely see how the thought of Phentermine increasing a person’s fight response can be the prevalent reason why random spurts of anger happen while taking the drug. My experience confirms this theory:

    As a Marine veteran with combat experience, naturally my fight-or-flight response has been fine-tuned to always choose the “fight” part of the spectrum. I am also medically diagnosed with depression and anxiety issues and it is because of my disorders that I have been prescribed to take 100mg of Zoloft daily for about five years now.

    When I started taking Phentermine, I was amazed by how effective it was when it came to aiding weight-loss and suppressing appetite. However, I also noticed that my mood was slowly declining throughout the days and, not only that, it seemed like I would get extraordinarily angry at the most trivial of things during the same amount of time. Honestly, it felt like I had reverted back to my old and violent-self, and while I attempted to balance out the issues by increasing my dosage of Zoloft to the maximum I am allowed by my doctor (200mg), I thought it to be counter-productive that I should have to increase a dosage of one medication just to try and balance another. To make a long story short, after a month and a half of taking Phentermine, I decided to stop taking it just this last Saturday.

    And wow! I must say that not only has my overall mood significantly increased in less than a week, but I can tell you that all of the things which made me extremely angry a month ago while taking Phentermine (i.e. work, simple mistakes, dropping things, losing things, etc.) no longer phase me, in the the slightest.

    It is because of this drastic change in mood that my opinion has become this: the Phentermine not only counteracted the Zoloft which had kept me in-check for five-years, it also exasperated my own fight-or-flight response to the point that not even my Marine Corps training, which taught me to seperate the important things from the unimportant, could help me

    Therefore, I urge those with previously diagnosed anger issues to strongly take into consideration the common side-effect of “phen-rage.”

    • Hi Donovan,
      Thanks for sharing your experience with us, it is very interesting to hear how phentermine effected you and the difference you noticed once you stopped. Good luck for the future! 😀

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