Phentermine

Potential Health Benefits of Phentermine

• Promotes healthy weight loss [2-38]
• Lowers blood pressure [39-45]
• Improves heart health [46-50]
• Treats sleep problems [51-52]
• Lowers cholesterol levels [53-55]

What is Phentermine?

Phentermine is used for a limited period of time (3 to 6 weeks) to significantly reduce weight in overweight and obese individuals. This FDA-approved weight loss medication belongs to a class of drugs known as sympathomimetic amines. It works by suppressing your appetite while increasing your energy expenditure. By stimulating the release of brain chemicals that will manipulate your mind to feel full with lesser food intake, phentermine helps achieve your weight loss goals without any adverse side effects. [1] This drug comes as tablets and extended-release capsules and is sold under the names Adipex or Suprenza.

How does Phentermine Work?

Phentermine is an anorectic drug, which means it is an appetite suppressant. The drug stimulates the release of chemicals, or neurotransmitters, in the brain. The neurotransmitters whose levels are increased by this drug are norepinephrine, dopamine, and serotonin.

Chemical Structure of Phentermine

Research on Phentermine

Promotes Healthy Weight Loss

The ability of phentermine to dramatically reduce weight without untoward side effects is backed by a number of high-quality studies:

1. 1. An analysis of several clinical trials found that phentermine can result in a weight loss of 3.6 kg at six months compared with placebo treatment. [2]
   2. In obese subjects, phentermine administration initially at 15 mg daily and slowly up-titrated to 37.5 mg daily resulted in a 13% reduction in baseline peak weight. [3]
   3. In obese or overweight patients with weight-related comorbidities, treatment with phentermine consistently demonstrated statistically significant weight loss after 56 weeks compared with placebo. [4-5]
   4. When combined with other weight loss drugs, phentermine can produce greater weight loss. [6-14]
   5. In one-hundred-eight obese women, continuous daily phentermine administration resulted in a mean weight loss of 27 pounds (12.2 kg) while intermittent phentermine (4 weeks on therapy and 4 weeks off of therapy) resulted in a mean weight loss of 28.7 pounds (13 kg). [15]
   6. Several studies also found that phentermine only reduces weight during the time that it is being taken. [16-22]
   7. When combined with topiramate, an anti-seizure drug, phentermine produced significant weight loss without any adverse side effects. [23-29]
   8. Studies suggest that phentermine promotes weight loss by inducing changes in eating behavior. [30-34]
   9. Studies found that overweight and obese patients as young as 3 years and as old as 88 years can be safely treated with phentermine. [35-36]
   10. An analysis of 6 studies found that patients using 15-30 mg of phentermine daily for 2 to 24 weeks had a mean total weight loss of 6.3 kg. [37]
   11. In healthy obese people, short-term phentermine administration significantly reduced weight and waist circumference without clinically problematic adverse events. [38]

Lowers Blood Pressure

Not only does phentermine reduces body weight but it also lowers blood pressure, making it beneficial for hypertensive patients:

1. 1. In overweight hypertensive patients, phentermine administration reduced blood pressure and was well tolerated. [39]
   2. In obese patients, phentermine treatment improved blood pressure and prevented the progression to hypertension. [40]
   3. The Swedish Obese Subjects (SOS) study found that phentermine reduced the incidence of hypertension by 2.6 times. [41]
   4. In overweight and obese individuals with type 2 diabetes, phentermine treatment was associated with a 5-mmHg decrease in diastolic blood pressure. [42]
   5. A recent phentermine clinical trial conducted in healthy obese patients reported a slight decrease in blood pressure. [38]
   6. In obese patients, administration of a 30 mg capsule of phentermine daily over a period of 12 weeks significantly reduced blood pressure. [43]
   7. In hypertensive patients, phentermine reduced systolic blood pressure by −7.5 to −11.8 mmHg. [44]
   8. In both lean and diet-induced obese mice, phentermine significantly reduced blood pressure. [45]

Improves Heart Health

Taking phentermine is also beneficial for cardiovascular health according to studies:

1. 1. Patients using phentermine had lower rates of hospitalization for acute myocardial infarction. [46]
   2. Phentermine increases heart rate due to its amphetamine-like side effect. [47]
   3. In overweight and obese adults with metabolic abnormalities, phentermine was associated with a slight increase in heart rate (0.1 to 1.3 beats per minute). [48-49]
   4. Since phentermine promotes weight loss, it can significantly reduce cardiovascular mortality for the following 4-5 years even in patients with pre-existing heart disease. [50]

Treats Sleep Problems

Evidence suggests that phentermine can help improve sleep quality and quantity in patients with sleep problems like obstructive sleep apnea, a sleep disorder characterized by involuntary cessation of breathing for brief periods of time (apnea) during sleep:

1. 1. In obese subjects with moderate to severe obstructive sleep apnea who were unable or unwilling to comply with standard treatment, administration of phentermine 15 mg plus extended-release topiramate 92 mg significantly reduced symptoms. [51]
   2. In obese adults, phentermine treatment reduced the incidence of apnea. [52]

Lowers Cholesterol Levels

Studies also found that phentermine can help improve cholesterol levels:

1. 1. In obese patients, phentermine administration resulted in lower total cholesterol and low-density lipoprotein (bad cholesterol) concentrations. [53]
   2. A review of the metabolic effects of phentermine found that this drug exerted favorable effects on lipid profile, especially on high-density lipoprotein (good cholesterol) and triglycerides. [54]
   3. In patients with abnormal lipid profiles, phentermine treatment was associated with significant improvements in blood levels of high-density lipoprotein (good cholesterol) and triglyceride as well as a net reduction in lipid-lowering medication use. [55]

Associated Side Effects of Phentermine

Phentermine side effects are very uncommon. There have been some side effects associated with the use of this drug wherein the patient had one of the issues listed below at some point while being on phentermine. However, these side effects weren’t confirmed to be associated with the treatment and could have been a coincidence and not related to the use of phentermine. Despite this, it was listed as a side effect associated with phentermine even though these associated side effects are very uncommon.

Side effects associated with phentermine may include the following:

• Constipation
• Dry mouth
• Erectile dysfunction
• High blood pressure
• Increased heart rate
• Insomnia
• Nervousness
• Sleeplessness
• Tingling or prickling feeling in the hands and feet
• Tremors

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