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Genric Name: phentermine [ FEN-ter-meen [ FEN-ter-meen]

Brand names: Adipex-P, Lomaira, Suprenza

Classification of substances: Anorexiants, CNS stimulants

What is Phentermine?

Phentermine is similar to amphetamine. It is a stimulant for your central nervous system (nerves and brain), which can increase your heart rate and blood pressure and reduce your appetite.

Phentermine can be combined with exercise and diet to combat overweight, particularly in those at risk for developing hypertension, high cholesterol or diabetes.

Phentermine can also be employed for other purposes not covered in this guideline.


Don't use Phentermine when you are breastfeeding or pregnant with the baby.

Phentermine is not a good choice when you suffer from glaucoma or thyroid hyperactivity, extreme heart problems and uncontrolled high blood pressure or advanced coronary artery disease, severe anxiety or addiction history.

Avoid using this medicine If you've taken an MAO inhibitor within the last 14 days, including linezolid and isocarboxazid, as well as methylene blue injection, phenelzine rasagiline, selegiline or tranylcypromine. A potentially dangerous interaction between drugs may happen.

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Before you Take this Drug

It is not recommended to use Phentermine If you are allergic to it or are suffering from the following:

  • An underlying background of heart diseases (coronary arterial disease, rhythm issues, congestive heart disease and stroke);
  • Extreme or uncontrolled blood pressure
  • Thyroid hyperactivity;
  • Glaucoma;
  • Extreme agitation or nervousness
  • A history of drug use; or
  • If you also take another diet pill.

Do not take Phentermine if you've used an MAO inhibitor in the last 14 days. A potentially dangerous interaction between drugs could occur. MAO inhibitors are isocarboxazid linezolid, Methylene blue injection rasagiline, phenelzine and tranylcypromine, among others.

Weight loss during pregnancy may affect the baby's development even if you're obese. Don't take Phentermine while you are expecting. Tell your doctor immediately if you find yourself pregnant while receiving treatment.

Do not breastfeed during this medication.

To ensure this medicine is appropriate for you, consult your doctor if:

  • The heart or coronary arterial disease
  • A heart valve disorder;
  • High blood pressure
  • Diabetes (your dosage of medication for diabetes could have to be adjusted) or
  • Kidney disease.

Phentermine is not permitted for use by anyone less than 16 years of age.

How to Take Phentermine?

Follow the exact dosage of Phentermine as directed by your physician. Follow the instructions on the prescription label and go through the entire medication guide or instruction sheets. The doctor might modify your dosage.

Doses are typically taken before or between 1 and 2 hours following breakfast. Follow the instructions of your physician for dosing with care.

Do not take Phentermine in large quantities or for longer than prescribed. Taking more of this drug won't improve its effectiveness and could create dangerous adverse, life-threatening side effects.

This medicine is intended for limited use for a short period. The effects of the appetite suppressant could fade away within a couple of weeks.

Phentermine could be a drug that can cause dependence. Misusing the prescription can lead to addiction, overdose, or even death. Selling or giving away this medication is against the law.

Get in touch with your doctor immediately If you suspect that this medication isn't working for you or if you have not lost more than 4 pounds in four weeks.

Don't stop taking this medication suddenly; you could experience uncomfortable withdrawal symptoms. Consult your doctor about how to effectively stop taking this medicine.

Keep at room temperature and free of heat and moisture. Close the bottle when not being used.

Details on Dosage

Usual Adult Dose for Obesity:

8 mg orally, three times a day, 30 minutes prior to meals, OR

15 to 37.5 mg taken orally every morning before breakfast or 1 to 2 hrs after breakfast.

Use A short-term (a couple of weeks) supplement to a plan of weight reduction that is based on behavioural modification, exercise and caloric restriction to manage exogenous weight gain in patients with an initial body mass index (BMI) of 30 kg/m2 or higher or a BMI of 27 kg/m2 or more when there are additional risks (e.g. diabetes, controlled hypertension, hyperlipidemia).

Usual Pediatric Dose for Obesity:

Age 17 Years and Older:

8 mg taken orally three times per day for 30 minutes prior to meals, OR

Between 15 and 37.5 mg once a morning before breakfast or 1 to 2 hrs after breakfast.

Use A short-term (a couple of weeks) as an adjunct to a program of weight loss based on behavioural modification, exercise and caloric restriction to manage exogenous obesity in patients who have first BMI (BMI) at or above 30kg/m2 higher or BMI of 27 kg/m2 or more when there are others risks (e.g. diabetes, controlled hypertension and hyperlipidemia).

What Happens If I Miss a Dose?

Do the medication as quickly as you can; however, avoid your missed dose in case later in the daytime. Don't take two doses at the same time.

What Happens If I Overdose?

Get medical attention immediately or contact the Poison Help line at 1-800-222-1222. A high dose of Phentermine can cause death.

Overdose symptoms can include panic, confusion, hallucinations, severe anxiety, nausea, vomiting, diarrhoea, stomach cramps and feeling depressed or tired or depressed, irregular heartbeats, low pulse, seizures or slow breathing (breathing could cease).

Avoid this

Avoid driving or engaging in hazardous activities until you understand how Phentermine affects your body. The way you react could be impaired.

Consuming alcohol while taking this medication could cause adverse negative effects.

Side effects of Phentermine

Contact a medical professional immediately in the event that you exhibit symptoms that you are experiencing an allergic reaction to the drug phentermine: hives and breathing difficulties, and swelling of your lips, face and tongue.

Phentermine may cause serious side effects. Contact your doctor immediately if you experience:

  • Feeling breathless being short of breath even after a moderate effort;
  • Chest pain, feeling like you might pass out;
  • Swelling in your feet or ankles;
  • Beats of your heart, or the sound of a fluttering your chest
  • Tremors, feeling restless, trouble sleeping;
  • Sudden changes in behaviour or mood and
  • Raised blood pressure, high blood pressure - extreme headache, blurred vision, pounding your neck or ears. Stress nasal bleeding.

Common negative side effects of Phentermine can include:

  • Itching;
  • Dizziness headache;
  • Dry mouth;
  • Unpleasant taste
  • Diarrhoea;
  • Constipation;
  • Stomach pain; or
  • An increase or decrease in sexual sex interest has decreased or increased.

This isn't a complete list of all side effects. Others could happen. Consult your physician for advice regarding the medical effects. You can report any side effects to the FDA at 1-800-FDA-1088.

Interaction With Other Drugs

Taking Phentermine in conjunction with other diet medicines like fenfluramine (Phen-Fen) and dexfenfluramine (Redux) could result in an uncommon lung disease that is fatal, known as pulmonary hypertension. Do not take Phentermine with other diet medicine without your doctor's approval.

Numerous drugs may be a cause of interaction with Phentermine. This includes prescription, over-the-counter medications, vitamins, and herbal supplements. The interactions of all drugs are not included in this list. Inform your doctor of all the medications you are currently taking and any medication you begin or stop taking.




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