Along with physical phentermine side effects such as dry mouth and insomnia, this medication can also cause emotional side effects such as low mood, anxiety and anger. In fact, increased anger, or dysphoria, due to phentermine is so common that it even has its own nickname: phen rage.
Phentermine affecting mood is a common side effect of this medication, with almost 40% of users experiencing phen rage, low mood or anxiety during weight loss treatment . However, day-to-day phentermine mood swings should not pose a danger to yourself or others.
Among this medication's reported side effects, phentermine anger issues are one of the most common with over 23% of patients reporting dysphoria at some point during treatment . This seemingly uncontrollable, sometimes irrational anger and frustration is colloquially referred to as “phen rage”.
Phen rage describes the feelings of frustration, impatience, hostility, irritability, and anger that patients feel while taking phentermine. In most cases, this anger is directed outwards in angry outbursts, shouting, and even physical destruction or violence.
If you have noticed that you are suddenly overreacting to situations or consistently in a bad mood since beginning phentermine, you may be experiencing phen rage.
Phentermine anger can sometimes be managed using the tips below (like giving yourself a time-out), but do not hesitate to contact your doctor if phentermine mood swings are interfering with your relationships or daily life.
Like most phentermine side effects, phen rage is usually worst at the beginning of treatment.
Using the experiences of Facebook support group members as a guide, phentermine anger and irritability can last anywhere from a few days to few weeks. Regardless of timing, if a bad mood from phentermine is interfering with your life or relationships, speak to your prescribing doctor.
There is no proven method to prevent phen rage, or any other phentermine side effect. Thankfully, this reaction does not occur in every patient. If you are concerned about phentermine-related anger, the below lifestyle strategies may help minimize your risk of developing phentermine mood swings.
It is not known exactly how phentermine affects the brain and produces its desired effects, but two possible explanations for phentermine mood swings and phen rage include:
Phentermine activates the limbic system and triggers the adrenal glands to release hormones associated with “fight or flight”.
This reaction is beneficial for weight loss because it promotes appetite suppression and hunger becomes a lesser priority. At the same time, extra glucose is released to boost energy and promote activity.
Unfortunately, the emotional side of sympathetic nervous system (SNS) activation is not as beneficial for the average dieter.
The body associates the hormones responsible for the above reactions – including adrenaline and norepinephrine – with stress. Even though the human body is an ornate & finely-tuned organism, biologically, it cannot distinguish between real stress, anger or fear and medication-induced CNS activation.
As a result, when phentermine kicks-in, the brain and body may start “helping” you get ready to fight even though there is no actual danger. In some people this can lead to phen rage, including irrational behavior and uncharacteristically extreme reactions.
Phentermine also tends to independently magnify users’ feelings – both positive and negative. Many users report that their reactions to situations become amplified, whether that is feeling high when happy, depressed when low, or rageful when bothered. This polarity is likely related to hormonal changes associated with SNS activation.
Quick, dramatic weight loss can also affect hormones. Dramatic weight loss causes fluctuations in hormone levels due to changing metabolic rate, different eating and exercise habits and decrease in body fat percentage.
Estrogen, for example, is produced in fat cells, so less adiposity often correlates lower levels of this sex hormone. Hormonal fluctuations can cause phentermine mood swings, in some way comparable to spells of irritability associated with PMS, pregnancy, perimenopause or menopause.
Side effects fueled by biological reactions like hormonal changes are hard to control, so overcoming phen rage is not always easy. However, some simple strategies can help you feel less angry and more in-control while taking phentermine.
If you have noticed phentermine anger bubbling up occasionally, try the below tips for how to avoid phen rage:
Sleep deprivation leaves people tense, irritable and prone to anger . So, insomnia combined with stimulant-related emotional changes can make the perfect cocktail for angry outbursts. Aim for 7-9 hours of quality sleep each night to keep hormones and phen rage in-check.
Timeouts are usually reserved for kids, but they can help avoid angry outbursts too. When you feel yourself working up to a breaking point, walk away and take a quick break. A few moments of quiet might provide some necessary clarity to deal with the situation at-hand without getting angry.
Family, friends and colleagues are likely to bear the brunt of your phentermine anger, so it is productive to tell them how phentermine affects your mood. If you have already experienced an outburst, explain how the things you may have said and done recently do not always represent how you really feel.
Breaking a sweat is a great way to relieve stress, boost endorphins and give you a positive outlet for the extra energy phentermine provides . When you feel your anger taking hold, harness that energy to go for a jog, dance it out or clean the kitchen.
Alcohol should be avoided while taking phentermine due to the increased risk of adverse side effects like hypertension, dizziness and lightheadedness . The disinhibition associated with drinking can also make you more likely to lose your temper, so potential phen rage is yet another reason to avoid alcohol with phentermine.
Although phen rage can strike as a result of seemingly trivial situations, identifying why these events result in angry outbursts can help to avoid future problems. If a specific person or situation is causing anger or resentment, find a calm moment to discuss your frustrations rather than let this frustration build up into an angry outburst.
Diet is an often-overlooked cause of phentermine irritability. To avoid “hangry” outbursts, eat regular nutritious meals full of a wide range of nutrients. Aim to plan meals and pack snacks ahead of time.
After a few days of rage irritability, frustration and impatience, some users consider supplements and herbs to manage phentermine mood swings. While natural remedies are not typically effective given the cause and severity of phentermine anger, some herbs and supplements with purported benefits for anger control and calming include :
However, it is not always safe to combine but herbs and supplements with prescription medications.
For this reason, always you check with your prescribing doctor and pharmacist before taking ANY supplement alongside phentermine. If appropriate, he or she can also offer medical solutions that provide more powerful relief.
Learn more about phentermine!
3. Johns Hopkins Medicine. (2018). The Effects of Sleep Deprivation.
4. Mayo Clinic Staff. (2018, March 08). Exercise and stress: Get moving to manage stress.
5. Drugs.com. (2019, January). Phentermine and Alcohol / Food Interactions.
6. American Addiction Centers. (2019). Treating Anger Disorders - Anger Management Treatment Options.