How to Get More Energy From Phentermine

Phentermine famously boosts energy, but for some users this much-anticipated lift never comes or wears off only a few weeks into treatment. If your phentermine stopped working and you are now left looking for other ways to increase energy, consider these dietary and lifestyle changes to give yourself a boost.

Does Phentermine Give You Energy?

Phentermine energyPhentermine works as a central nervous system stimulant and possesses a chemical structure similar to amphetamine. As such, this medication boosts energy while also amplifying feelings of concentration and alertness to help users remain focused on their weight loss goals and avoid snacking. 

In the first couple of days, many patients experience a buzz or “wired” feeling from phentermine. However, this sensation typically levels-out to a less intense, more sustainable buzz as the body adjusts to phentermine. As a result, most patients enjoy the extra energy to increase physical activity and facilitate weight loss. Unfortunately, some users never experience any boost of energy while taking this medication. 

According to an online poll of 177 current phentermine users, over half of phentermine users always or sometimes experience an energy boost, while 26% say they have never had extra energy from phentermine.

Phentermine and Energy

Given individuals’ vastly different experiences with phentermine and energy, it is understandable why so many people seek information about how to boost energy while taking phentermine. If you are looking for ways to boost energy during your phentermine weight loss journey, try some of the tips below.

How long does the energy from phentermine last?

Like most effects of phentermine, the phentermine energy boost lasts for a different amount of time in each person. This medication is fully absorbed in 4-6 hours, but its effects can be felt for significantly longer [1]. In terms of phentermine and energy specifically, most patients feel the phentermine energy boost for about 10-14 hours [2]. This is why doctors and pharmacists recommend taking your last pill no later than 8-10 hours before bedtime to minimize the risk of stimulant-related insomnia.

How to Get Energy from Phentermine

Phentermine stimulates the central nervous system, but that does not mean the medication is universally energizing. If phentermine doesn't give you energy, or doesn't give you the boost you hoped for, there are several things you can do to get a phentermine energy boost.

1. Prioritize Sleep

Prioritize sleepSleep is a simple but powerful solution to your energy crisis. With ever-busier schedules, it is common to cut a few hours of sleep out each week to make time for other activities. However, sleep deprivation can wreak havoc on your health, not to mention your energy levels. Aim for 7-9 hours of sleep per night.

2. Exercise

Even though it may sound counterintuitive at first, exercising is a great way to boost energy naturally. Moving around gets your blood flowing through your brain and body, which increases energy!

 Consider Interval TrainingConsider interval training

Quick, intense workouts in the form of interval training are beneficial for both energy levels and fat loss. Interval training, also called “burst training”, consists of quick intervals (30-60 seconds) of high-intensity exercise alternated with slightly longer intervals (3-4 minutes) of lower intensity work [3].

 Stretch It Out

An invigorating stretch session can help you feel more energized right away. Stretching increases circulation to provide the brain and body with much-needed oxygen and nutrients. Just a few minutes per day can make a big difference in your energy levels [4].

3. Take Multiple, Short Breaks

Take multiple short breaksFor most adults, long work hours with too few breaks are the day-in, day-out reality. However, this common pattern is not good for weight loss, energy levels or productivity.

Make a habit out of seizing opportunities throughout the day to take short breaks. Go to a restroom on another floor, stand up to refill your glass of water regularly, or go and talk to a colleague face-to-face instead of sending an email. These are all great ways to burn extra calories, stretch your legs, rest your eyes and clear your head for a few minutes.

In fact, researchers at the University of Illinois at Urbana-Champaign found that taking several short breaks improves performance on extended tasks, such as a studying for a test or getting through a long shift at work. In short: taking short, periodic mental breaks actually improves focus [5]!

4. Drink More Water

Drink more waterEven mild dehydration zaps energy, so drinking enough water is a must for keeping energy levels high. Research shows that just 1-2% dehydration causes headaches, fatigue and difficulty concentrating in women, and makes men feel more fatigued, tense and anxious. To combat dehydration-related fatigue, aim for about two liters (64 ounces) of water per day [6]. Drink extra fluids if you sweat more due to exercise, extreme weather or other reasons.

5. Prioritize Protein

Prioritize proteinProtein is an important energy source for weight loss. It is a complex and lasting fuel source that keeps you full the longer than pure carbohydrates, plus promotes the creation and repair of lean body tissue. Given the more-sustained energy that protein provides, it also helps regulate blood sugar to prevent spikes and crashes. Maintaining consistent, steady blood sugar levels makes you feel more energetic and less lethargic overall. 

Foods like eggs, chicken breast, fish, legumes and low-fat dairy are all good sources of protein that will help keep your energy up during weight loss. 

6. Plan Your Meals

Plan your mealsPlan to eat three light, nutritious meals per day, plus 2-3 small snacks. Eating 5-6 times per day can help boost energy because it keeps your body fueled and minimizes low blood sugars. Always start the day off right by eating breakfast. Many dieters skip their morning meal in hopes of saving a few hundred extra calories, but taking the time to prepare and eat a nutritious breakfast helps set the tone for the rest of the day. Follow a filling breakfast with a well-rounded lunch and light dinner.

For snacks, indulge in a 100-200 calorie mini-meal that provides a combination of fiber, healthy carbs and protein.

7. Include Omega-3 Fatty Acids

Include Omega-3 fatty acidsOmega-3 fatty acids reduce inflammation, combat depression, improve mood and memory – all of which positively affect energy levels. 

Good food sources of omega-3 fatty acids include: cold water fish (e.g. salmon or tuna), walnuts, flaxseeds, leafy green vegetables, beans and edamame. Work to incorporate more of these foods into your meals and snacks to boost energy and weight loss.

8. Avoid Acidifying Foods

Avoid acidifying foodsUrinary pH affects how much phentermine the body uses. Under normal circumstances, about 30% phentermine is excreted unchanged. However, patients with an acidic urinary pH excrete a much higher 60% unchanged in 48 hours. On the other hand, those with an alkaline urinary pH metabolize more of the medication and excrete just 7% of the dose unchanged in 48 hours [7]. So, maintaining an alkaline (basic) urinary pH may help your body use phentermine more efficiently.

9. Eliminate Caffeine

Eliminate caffeineGeneral advice is to avoid coffee while taking phentermine given the potential for a dangerous reaction between two stimulants. You may be surprised to learn, however, that cutting coffee is also beneficial for energy levels. This is because habitual caffeine consumption increases natural feelings of fatigue if the body becomes too reliant on the stimulant to provide energy. Coffee also decreases urinary pH, which causes phentermine to be expelled from the body sooner. So, skipping your mid-morning latte can actually help you feel more energized by phentermine itself.

10. Let Yourself Yawn

YawnYawning is not always socially acceptable, but it is your body’s natural energy boost. When you open your mouth and inhale (as you do while yawning) it provides an extra boost of oxygen to increase alertness and energy.


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4. UC Davis Student Health and Counseling Services. (2014, April 29). Why Stretching is Extremely Important. Retrieved from 

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