Phentermine vs Ozempic

Written by Clark on November 18, 2024 — Medically Reviewed by Clark

Phentermine vs Ozempic weight loss results, side effects

Phentermine has been one of the most popular and practically utilized drugs for weight loss medication for over 60 years and it shows efficacy as well as cost efficiency in medication.

But at present there are a few relatively newer drugs under the GLP-1 agonist class, and one of the most widespread is Ozempic (semaglutide).

In this article, more details concerning the two drugs will be provided to help you distinguish between Phentermine and Ozempic.

Injection vs Pill

Ozempic is available in the form of a multi-dose prefilled injectable pen. There are three types of Ozempic pens:

  1. Red label (0.25 mg and 0.5 mg)
  2. Blue label (1 mg)
  3. Yellow label (2 mg)

It can also be self-administered as a weekly injectable subcutaneous drug in a specific location on the abdomen, outer thigh, or upper arm using an auto-injector, which directly places the molecule into the fatty tissue of the area targeted.

Phentermine comes only in a once-a-day release tablet and is marketed as caps/capsules or tablets or Orally disintegrating tablets. Lomaira is the least concentrated preparation of phentermine and should be swallowed with water half an hour before every meal three times daily.

Diabetes vs Weight Loss

Ozempic and Phentermine have different approved uses:

  • Ozempic: It has been taking by many people since it provided more effective weight loss solutions even though it was not designed for that purpose. This has been recommended for glycaemic control in adult patients with T2DM. But for the management of diabetes, the medicine is prescribed to slim down. They also advise that it is suitable for use by those who have heart disease to minimize the likelihood of severe cardiovascular crisis. Ozempic may also gain approval for kidney health benefits soon.
  • Phentermine: Suggested to be taken for a duration of up to 12 weeks in the treatment of obesity in persons with an age of 17 years and above. It has to be taken only for 3 months at a time, but if it is effective, doctors can extend the period. Phentermine is also used in combination with the anti-seizure medicine topiramate under the name Qsymia for weight loss over the course of years.

Different Methods of Weight Loss

Those who are using Ozempic or phentermine, often complain about a reduction in appetite. Despite this, both drugs can lead to weight loss but this occurs in different ways.

  • Ozempic acts like a native hormone released in the small intestine known as GLP-1. It has many effects on the body which could be of interest in reducing blood glucose (sugar) levels. A couple of these can help you lose weight. Among them is the impact of Ozempic on the food intake control section of the brain. As it also reduces the movement of food through the stomach.
  • Phentermine is the stimulant class of drugs, related chemically to amphetamine. It is supposed to work by increasing the production of brain chemicals that facilitate the management of hunger levels.

A reduced appetite from both drugs means that you eat fewer amount of calories. This may cause weight loss. However, for the best effects, combine with a healthy diet and frequent exercise.

Varying Side Effects

Another distinction is that Ozempic and Phentermine may have different adverse effects. Ozempic’s side effects predominantly impact the digestive tract. Some of the more general side effects that most patients who take phentermine experience result from the actions that this drug has on the blood vessels and nervous system of the body.

  • Ozempic: This includes nausea, vomiting and diarrhea, especially with initiation or with initiation of a higher dose. They often get better on their own, and a change in diet should help. Some very serious, and less frequent side effects include problems with the pancreas and the gall bladder.
  • Phentermine: It can also bring about side effects like insomnia, headaches, as well as tremor. It also raises both blood pressure and pulse rates and this can be very risky when dealing with cardiac patients.

Ozempic or phentermine may not be suitable for you in some circumstances. For example, any person with a history of pancreatitis should not take Ozempic. Phentermine is contraindicated in persons with hyperthyroidism, that is persons with an overactive thyroid gland. Their heart rate may already be high.

Is Ozempic Safer?

People with heart problems should avoid using phentermine. This implies that it should be avoided as it leads to injury or rather cause harm. The active ingredient in Ozempic called semaglutide provides cardiovascular advantages to anyone with heart disease, not only patients with diabetes.

As side effects, phentermine may lead to a rise in heart rate and high blood pressure. This can have very serious effects on persons such as those with heart diseases. However, further research is required to understand this risk. According to certain clinical investigations, it has been recommended that loss of weight due to phentermine has positive effects on blood pressure. If you have heart issues, your doctor may not even prescribe this drug as a means of being on the safe side.

That means that people with, for example, heart disease might try Ozempic. The current study has established the efficacy of this drug in alleviating a moderate cardiovascular event in patients with both Type 2 diabetes and heart complications.

Expected Weight Loss

Analysis of results based on people who use Phentermine shows that those who are overweight or obese can shed between 5% to 10% of their body weight in 3 to 6 months. Another observational study reported that patients who have used phentermine for over one year lose more weight. This was compared to persons who used it for a shorter amount of time.

During the initial Ozempic clinical studies, persons with Type 2 diabetes who received the 1 mg Ozempic dose lost around 10 pounds after 30 weeks (7 months). The 2 mg (maximum) dose has been demonstrated to result in around 15 pounds of weight loss after 40 weeks (9 months). However, it is not uncommon for persons using Ozempic to report losing much more weight.

Switching Medications

Yes, it is possible to make a switch from taking phentermine to ozempic. As explained above, Ozempic is used to treat type 2 diabetes. However, it has been frequently applied in that sense for managing weight loss in individuals who are not diabetic. For people with lower body weights, Ozempic levels in the body may be even higher.

If you are not satisfied with the outcomes of phentermine or if you need a permanent treatment, your doctor may prescribe you Ozempic (or Wegovy).

Can I Take Both? 

You may be able to take Ozempic and Phentermine together. This has not been studied, thus it is unclear whether the combination is safe. We don’t know if taking them together leads to greater weight loss. There is a shortage of research. As a result, phentermine comes with a caution against mixing it with other weight-loss drugs.

Even so, your doctor may advise you to take Ozempic and Phentermine together. Tell them if this combination causes new or worsening adverse effects.

Conclusion

Therefore, Ozempic and Phentermine work differently and are authorized for different purposes but help lose weight. Ozempic is an insulin-sensitizing drug that affects appetite and reduces the rate of digestion whereas Phentermine is an appetite suppressing, central nervous system stimulating drug indicated for short term use in management of obesity. They also vary in delivery, side effects, patients with heart disease, and insurance. A healthcare provider must come in handy to compare features such as the health history, costs, and target weight loss.

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