Phentermine For Weight Loss

Phentermine is a new anti-obesity drug that big pharma is heavily promoting to combat the obesity epidemic in the US in recent years.

Today, I will be discussing Phentermine, its uses, dosage, and side effects.


More than 35% of American adults were classified to be clinically obese being classified as obese (1).

This means that out of every three people you meet today, one is statistically likely to be obese.

Are you are someone who is obese, overweight or are seeking information for someone who is?

If so, this article is exactly what you need to read.

What Is Phentermine?

Phentermine is a weight loss drug for obesity. It requires a doctor’s prescription and is only safe for short-term use.

Phentermine was approved by the FDA to be used by people over the age of 16 for up to 12 weeks This was done back in 1959 (2).
Phentermine’s molecular formula is C10H15N and the chemical name is Duromine; 2-methyl-1-phenylpropan-2-amine. (3)

This is a sympathomimetic and stimulant that works on the central nervous system.

The intended purpose of this drug is to activate the appetite suppressant property of the brain. It also helps boost energy levels and fat breakdown.

How Does Phentermine Work?

is an anti-obesity prescription medication.

It’s prescribed only in extreme cases where fast weight loss is needed.

It also requires a complimentary workout and diet plan to be effective.

Like most weight-loss products, it’s not a miracle weight-loss pill. It needs you to exercise to burn fat and lose weight to work effectively.

It works by boosting the release of the neurotransmitter, norepinephrine.

The neurotransmitter is secreted in fight-or-flight situations. In Phentermine, it reduces your hunger urges by suppressing your appetite.

This drug also releases Adrenaline outside of the brain, speeding up the breakdown of fat.

What Does Phentermine Do To The Body?

Phentermine boosts the catecholamine release in the body which helps to block hunger signals in the brain.

The release of catecholamine hormone can help decrease appetite and increase heart rates.

This potent stimulant can help treat obesity, high blood pressure, heart problems, and diabetes.

Also, it can support your nervous systems which can help curb your craving and emotional eating.

Moreover, it can reduce fat and starch absorption, preventing weight gain in the body.

Why Do Doctors Prescribe Phentermine?

You can find Phentermine in most countries, but it’s a strict prescription-only medication.

Phentermine Requires A Doctor's Prescription

In the US and many other countries, it’s classified as a Schedule IV controlled substance and a controlled drug.

The reason for this classification is because of its similarities to Amphetamine.

Phentermine is the go-to prescription for doctors who have patients with obesity.

If exercising isn’t possible or not showing results, doctors prescribe this drug.

The brands that contain Phentermine include:
  • Sentis
  • Qsymia
  • Razin
  • Suprenza
  • Redusa
  • FastinLomaira
  • Terfamex
  • Pro-Fast
  • Adipex
  • Duromine
  • Ionamin
  • Acxion
  • Elvenir
  • Panbesy

What Is The Dosage Of Phentermine Like?

The doctor is the one who decides how much of this drug you need to take.

For most patients, its one or two pills a day, an hour before breakfast. The doctor may also prescribe three smaller doses throughout the day instead.

One thing to remember is that you can’t take any other appetite suppressants when on this drug.

Another fact is that you aren’t supposed to take this for more than a few weeks at a time.

Taking it regularly for an extended period can damage your health. It also reduces the effectiveness of the drug.

I found this drug to be at its most potent point for the first week of use.

Should You Get A Prescription For Phentermine?

Who wouldn’t want fast weight loss?

Well, while the benefits are quite evident, there are some side effects of this pill that warrant caution.

But before we discuss the side effects of Phentermine, let’s look at if you can get a prescription.

To get a prescription for this drug, you need to:
  • Be clinically obese
  • Find supplements and other weight loss aids to be ineffective
  • Not be on certain other drugs known to cause adverse interactions
  • Be low-risk of being affected by drug addiction
  • Not have health issues like heart problems, high blood pressure, etc.
  • Not be planning to get pregnant, pregnant, or breastfeeding

Phentermine Side Effects:

Now for the side effects of Phentermine.

Before I mention the list of side effects you may experience after using this drug, here’s an interesting fact:

In the 90s, a drug called Pondimin was found to cause pulmonary hypertension, dyspnea, heart valve disease, and cardiac fibrosis.

This led to its withdrawal from the US market in 1997. The damages caused were calculated to be over USD 13 billion.

The interesting fact is that Pondimin combined two drugs, Fenfluramine and Phentermine.

So, while Phentermine, by itself, is still prescribed, this combination turned out to be fatal for many of its users.

Phentermine Side Effects

And as for the side effects of this prescription drug, here they are:
  • Feeling dizzy or faint
  • Finding it difficult to pass stool
  • Swollen feet or lower legs
  • Tingling or numb sensation in the extremities
  • Change in the sense of taste
  • Feeling weak
  • A heightened sense of well-being
  • Reduced ability to work out and exercise
  • Shakes or trembling of hands or feet
  • Skin conditions like redness, itching, rashes, hives or welts
  • Getting a dry mouth
  • Irregular/changing heartbeat
  • Headaches
  • Chest pains and difficult breathing
  • Difficult speaking, walking or thinking
  • Hair Loss


I would personally stay away from drugs like Phentermine unless they have been recommended by a Doctor. For weight loss benefits, I would rather look at OTC phentermine alternatives which produce phen-like results without any side effects


Is Phentermine Dangerous For Body?

Yes, Phentermine is dangerous for a human body.

Can I Drink Coffee While Taking Phentermine?

Yes, you can. However, you need to limit your coffee consumption while using Phentermine. People with cardiovascular problems and high blood pressures should prevent caffeine drinks and beverages while using phentermine.

Can I Drink Alcohol While Taking Phentermine?

Ideally, you should limit alcohol consumption to prevent various health issues including obesity. However, while you are taking Phentermine, you should not consume alcoholic drinks.

Is Phentermine Detected During a Drug Test?

It may give false-positive results in a urinalysis test due to similarities with an amphetamine. Also, it may give positive reports while getting a military drug test.

Are There Any Long Term Side Effects Of Phentermine?

Yes, it does have long-term side-effects, and some of them are already mentioned in the side-effect section.

Can Phentermine Kill You?

It might kill you. Phentermine may cause heart failure, uncontrolled high blood pressure and many more.

How Does Phentermine Help in Weight Loss?

Phentermine can help suppress appetite that can limit the production of fat in the body. This might help with weight loss.

Is It Safe To Take Phentermine On Empty Stomach?

It might be safe as some brands of phentermine should be taken with empty stomach 30-40 minutes before breakfast.

About Michelle

Michelle is the senior most expert who writes for this website. After completing her graduation and 10+ years of practice, Michelle has been involved and known for a lot of her philanthropy work. Michelle loves spending time researching and writing her papers. She occasionally writes for us and we are extremely proud to have her as one of our editors. Follow me on Linkedin