This article discusses how phentermine works to help you lose weight.
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What Is Phentermine?
Phentermine is often prescribed to promote weight loss in people with obesity or overweight status with additional health problems.

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Typically, it will be recommended if you have already tried lifestyle changes to lose weight.
This medication combo is marketed under the name Qysmia.
Unlike phentermine as a single-agent therapy, this combination is approved for long-term weight management.
How Does Phentermine Work in the Body?
Phentermine belongs to a class of medications called indirect sympathomimetics.
Sympathomimetics activate thesympathetic nervous system.
Indirect sympathomimetics act indirectly on different receptors.
Phentermine has been shown to work in the central nervous system to help reduce appetite.
Studies have shown that it acts on thehypothalamus.
Phentermine stimulates the release of chemical neurotransmitters in the brain, such as norepinephrine, suppressing appetite.
This medication should be used alongside a reduced-calorie diet and regular exercise.
How Long Does It Take to Work?
However, it may take a few weeks to see some weight loss.
How to Take Phentermine
Phentermine comes as a tablet or extended-release capsule.
Both dosage forms should be taken by mouth.
Lomaira is usually taken as 8 milligrams (mg) three times daily 30 minutes before meals.
Taking this medication late in the day may cause trouble sleeping.
Take phentermine as directed by your healthcare provider.
Who Can Take Phentermine?
Do not take it during or within 14 days of MAOI therapy.
You should also avoid taking phentermine if you are pregnant or nursing.
Summary
Phentermine is a prescription medication that can help promote weight loss.
It works in the central nervous system to stimulate certain chemicals that help suppress appetite.
This can include making a nutritious eating plan or adding more physical activity to your routine.
Talk to your healthcare provider if you are taking phentermine and do not notice any effects.
Frequently Asked Questions
Phentermine should be avoided during pregnancy.
It can potentially harm the fetus due to weight loss.
Medications can be an effective aid for people with obesity, but they are not a cure-all.
Alcohol can worsen phentermines side effects.
The author would like to recognize and thank Ghassan Alyaseen for contributing to this article.
DailyMed.Label: Adipex-P- phentermine hydrochloride tablet, Adipex-P- phentermine hydrochloride capsule.
Bray GA, Ryan DH.Update on obesity pharmacotherapy.Ann N Y Acad Sci.
2019;27(4):591-602. doi:10.1002/oby.22430
Food and Drug Administration.Qysmia label.
2013;21(11):2163-2171. doi:10.1002/oby.20584
Food and Drug Administration.Phentermine label
DailyMed.Label: Lomaira- phentermine hydrochloride tablet.