Phentermine for Weight Loss


Phentermine for Weight Loss
Written by Dr. Gary Kawesch

As studies for chronic obesity continue to evolve, one thing that hasn’t changed is the importance of diet and exercise. But unfortunately, despite all the hard work at the gym and diligent efforts to eat healthier, many patients who suffer from obesity still have trouble losing weight. In fact, according to, 1 out of three patients usually end up regaining their unwanted weight after 5-6 months, which is generally the time frame where they should be losing 5 to 10 percent of their weight.

Over the years, certain OTC weight loss drugs have provided patients a much-needed advantage in helping them lose and manage their weight. Unfortunately, although these weight loss alternatives boast that they can produce a significant decrease in body fats and longer-lasting results in weight management, many fall short of expectations and are usually full of unnecessary additives that are unhealthy to the body. And since these medications are broadly used for everyone, many patients find themselves experiencing serious side effects as each of their unique body types react differently to the weight loss drugs.

However, an FDA-approved weight loss medication is proven to help anyone suffering from chronic obesity and does so naturally without extra additives. But unless you’ve visited a licensed physician certified in treating weight loss, you’ve probably never heard of it before. If that is the case and you’re still having trouble managing your weight, then it may be time to ask your primary care doctor about the weight-loss medication, Phentermine.

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What is Phentermine?

Phentermine (also known as Adipex-P) is an appetite suppressant that was first approved for weight loss by the FDA in 1959, making it the oldest weight loss medication used today. It was first used to help provide short-term weight loss treatment of 12 weeks or less until a newer version (Phentermine-Topiramate) was approved again by the FDA in 2012 for long-term use of a year or more.

Research has shown that Phentermine can stimulate a 5% to 10% loss of body mass in as little as 12 weeks when combined with a low-calorie diet and strenuous exercise. In addition, Phentermine is a relatively inexpensive medication that is affordable enough to purchase without insurance by patients with lower income. Due to its effectiveness and reasonable pricing, physicians have popularly recommended Phentermine supplements as an effective weight loss treatment for patients suffering from obesity for the past ten years, making it the most commonly prescribed weight loss medication today.

How Does Phentermine Work for Weight Loss?

Phentermine is an anorectic that works to decrease hunger by triggering the release of neurotransmitters (norepinephrine, serotonin, and dopamine) to the part of the hypothalamus that controls appetite. As the level of chemical neurotransmitters increases and affects your central nervous system, your desire to overeat decreases.

However, patients using Phentermine as an appetite suppressant may build a tolerance after long-term use, so a physician may need to make adjustments to the prescription for patients to attain the best Phentermine weight loss results.

Who Are The Best Candidates To Take Phentermine For Weight Loss?

Typically, overweight and obese adults with a body mass index (BMI) over the 27- 30 kg range dealing with other weight-related conditions such as hypertension and diabetes are the only candidates who should take Phentermine as a weight loss drug. However, if you’re simply trying to lose a few pounds, you will need to talk with your physician about other alternatives to help with your weight-loss goals.

How Should This Medicine Be Used?

Like any other prescription diet pills, Phentermine-Topiramate should be taken by the mouth once a day, at least 1 hour before or after breakfast. If you’re using sustained-release capsules, take your dose 10 to 14 hours before bedtime. Otherwise, waiting too late in the day to take Phentermine can increase the risk of insomnia.

You should also avoid crushing or chewing the sustained-release capsules. Since the capsules are designed to slowly dissolve and release the medication in your stomach, chewing or crushing the pill can release Phentermine all at once and cause adverse side effects.

If you’re using dissolvable tablets, you can take the dose once a day without food. Make sure the tablet fully dissolves on your tongue before swallowing it.

Your dosage and the duration of treatment will depend on how your body responds to Phentermine. A physician specializing in using Phentermine at a weight loss clinic can determine the most appropriate dose to fit your body type and adjust the quantity of your prescription if necessary as you progress through treatment. Always consult your doctor about any changes in your body’s response so they can discuss the safest ways to use Phentermine as you continue through the program.

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Is Phentermine For Weight Loss Safe?

The FDA approved Phentermine as a safe short-term weight loss medication, while Phentermine-Topiramate has been proven effective as a long-term treatment for a year or more. However, patients should avoid taking Phentermine if they:

  • Have a cardiovascular disease
  • Are sensitive to stimulant drugs
  • Are taking monoamine oxidase inhibitors
  • Have a history of substance abuse

Because Phentermine also works as a stimulant, regular exercise is essential to work off the extra energy so you can burn calories more efficiently. Make sure to stick to a manageable daily exercise routine to safely work off that energy while taking Phentermine during your treatment.

Phentermine Side Effects

As it is with every medication, using Phentermine weight loss pills can cause common side effects, which include:

  • Increased heart rate
  • Constipation
  • Dry mouth
  • Sleeplessness
  • Nervousness
  • Tingling in the hands and feet

Malnourished or severely ill adults may experience breathing problems after using Phentermine. In some cases, patients taking Phentermine have also reported experiencing headaches as their bodies adjust to the treatment. Therefore, your physician may recommend that you use caution when driving or performing other hazardous activities until you know how Phentermine affects you.

Before Taking This Medicine

You will need to make sure that your body is healthy enough to ingest Phentermine to avoid other medical complications, so it is very important to discuss your medical records with your doctor before taking the medication. Inform them of any history of heart disease, high blood pressure, glaucoma, and substance abuse, as Phentermine can also enhance these conditions. Patients suffering from these conditions will need to review other weight loss options in order to maintain their physical health.

At Renew Vitality, we specialize in hormone replacement and weight loss therapy to help treat and manage medical weight loss. We offer hormone replacement options such as Wegovy, Ozempic, and Phentermine treatments to help overweight patients change their lifestyles so they can naturally achieve healthy weight loss goals and improve their overall health. Contact us at 1-800-785-3945 to schedule an appointment with one of our licensed hormone specialists and begin building a better version of yourself today!.

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Frequently Asked Questions

If possible, take the dose as soon as you can remember. However, if it is too late in the day, skip the missed dose altogether to avoid taking two doses in less than 24 hours.

Patients may feel a sense of tiredness or fatigue as Phentermine may cause periods of overstimulation which may lead to sleepless nights. Other side effects of Phentermine may also include drowsiness and low energy levels. If you feel fatigued or have a drop in energy from taking Phentermine, you should consult your physician immediately, as the symptoms may be a sign of an underlying medical condition.

Phentermine is typically prescribed as a part of a weight loss plan that incorporates exercise and a fat-burning diet, so you must take Phentermine for at least 12 weeks to achieve the best weight loss results. However, some results may vary depending on the patient’s body type, dieting, and exercise regimen.

For rapid weight loss with Phentermine, physicians recommend eating a high protein diet and a healthy amount of fiber. You should also incorporate increased intakes of fruits, vegetables, vitamins, minerals, and other nutrients to round out the diet. It’s also important to stick to a standard exercise regimen, drink plenty of water, and get adequate sleep so that your body can recover and burn more fat during the weight-loss program.


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