Fastin (Oral)

Phentermine is used as part of a short-term plan, along with a low calorie diet, to help with weight loss. It is for obese patients who have not been able to lose weight through diet and exercise alone. Phentermine is in a group of medicines called appetite suppressants.

You can only get this medicine with a prescription from your doctor.

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and does not cause any unwanted effects.

Do not use phentermine if you are also using similar medicines such as benzphetamine, diethylpropion, mazindol, phendimetrazine, Bontril®, or Didrex®. Do not use this medicine if you also take an MAO inhibitor (MAOI), such as isocarboxazid (Marplan®), phenelzine (Nardil®), selegiline (Eldepryl®), or tranylcypromine (Parnate®), or if you have used an MAOI within the past 14 days. Using these medicines together may cause serious unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to prevent getting pregnant. If you think you have become pregnant while using this medicine, tell your doctor right away.

This medicine may be habit-forming. If you think this medicine is not working properly after you have taken it for a few weeks, do not increase the dose. Instead, check with your doctor.

Call your doctor right away if you notice a decrease in your ability to exercise, or if you faint, have chest pain, swelling of your feet or lower legs, or trouble with breathing. These may be symptoms of a very serious heart or lung problem.

This medicine may cause some people to become dizzy, lightheaded, or less alert than they are normally. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or not alert.

This medicine may affect blood sugar levels. Diabetic patients may notice a change in blood or urine sugar tests. Check with your doctor if you have any questions.

Avoid drinking alcohol while you are using this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription and nonprescription (over-the-counter) medicines, dietary supplements, herbal remedies, or medicines for appetite control, asthma, colds, cough, hay fever, and sinus problems.

In deciding to use a medicine, you and your doctor will need to weigh the risks of taking the medicine against the benefits it may provide. For this medicine, consider the following:

Allergies

Inform your doctor if you have ever experienced any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know if you have any other allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Phentermine is not recommended for children aged 16 years and younger. Its safety and effectiveness have not been established for this age group.

Geriatric

Current studies have not shown any specific problems in elderly patients that would limit the usefulness of phentermine. However, older adults are more likely to have age-related liver, kidney, or heart issues, which may require caution and an adjustment in dose for those taking phentermine.

Breast Feeding

Studies involving breastfeeding women have shown harmful effects on infants. You should either be prescribed an alternative to this medication or stop breastfeeding while using this medicine.

Interactions with Medicines

Some medicines should never be used together, while in other situations, two different medicines may be used together even if an interaction might occur. In such cases, your doctor may want to adjust the dose or take other precautions. It is very important that your healthcare professional knows if you are taking any of the medicines listed below. The following interactions are chosen based on their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following is not recommended. Your doctor may decide not to treat you with this medication or change some of your other medicines.

• Furazolidone
• Iproniazid
• Isocarboxazid
• Linezolid
• Methylene Blue
• Moclobemide
• Nialamide
• Phenelzine
• Procarbazine
• Rasagiline
• Safinamide
• Selegiline
• Sibutramine
• Tranylcypromine

Using this medicine with any of the following is usually not recommended, but may be necessary in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you take one or both of the medicines.

• Iobenguane I 131
• Venlafaxine

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken around mealtime or with certain types of food due to potential interactions. Using alcohol or tobacco with some medicines may also cause interactions. Talk to your healthcare professional about how to use your medicine with food, alcohol, or tobacco.

Other Medical Problems

Other medical issues might affect how you can use this medicine. Be sure to inform your doctor if you have any other medical problems, especially:

• Agitated state (very nervous or anxious) or
• Arrhythmias (abnormal heart rhythms), history of or
• Arteriosclerosis (hardening of the arteries), serious or
• Congestive heart failure, history of or
• Drug abuse or dependence, history of or
• Glaucoma or
• Heart or blood vessel disease (e.g., coronary artery disease), history of or
• Hypertension (high blood pressure) that is not controlled, history of or
• Hyperthyroidism (overactive thyroid) or
• Stroke, history of—Do not use in patients with these conditions.

• Allergy to tartrazine—Suprenza™ contains tartrazine. Patients with this allergy may have an allergic reaction.

• Heart valve disease or
• Hypertension (high blood pressure) or
• Pulmonary hypertension (elevated pressure in the lungs)—Use with caution. This medicine may worsen these conditions.

• Kidney disease—Use with caution. The effects may be stronger due to slower removal of the medicine from the body.

Along with its needed effects, a medicine may cause some unwanted effects. Not all of these side effects may occur, but if they do, they may require medical attention.

Check with your doctor immediately if any of the following side effects occur:

Rare

• Seeing, hearing, or feeling things that are not there
• severe mental changes

Incidence not known

• Chest pain
• decreased ability to exercise
• dizziness
• fainting
• fast, irregular, pounding, or racing heartbeat or pulse
• headache
• numbness or tingling in the arms or legs
• swelling of the feet or lower legs
• trembling or shaking of the legs, arms, hands, or feet
• trouble breathing
• trouble with thinking, speaking, or walking
• weakness

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Your health care professional may also have ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue, are bothersome, or if you have any questions about them:

Incidence not known

• Decreased interest in sexual intercourse
• difficulty having a bowel movement (stool)
• dry mouth
• false or unusual sense of well-being
• hives or welts, itching, or skin rash
• inability to have or keep an erection
• increased sexual ability, desire, drive, or performance
• increased interest in sexual intercourse
• loss of sexual ability, desire, drive, or performance
• redness of the skin
• unpleasant taste

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Adipex
• Adipex-P
• Atti-Plex P
• Fastin
• Ionamin
• Lomaira
• Phentercot
• Phentride
• Pro-Fast

Available Dosage Forms:

• Tablet
• Capsule

Therapeutic Class: Appetite Suppressant, Centrally Acting

Chemical Class: Amphetamine Related

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. If you take too much of this medicine, it may become habit-forming (causing mental or physical dependence).

This medicine is available in four forms: capsules, disintegrating tablets, extended-release capsules, and tablets. Carefully follow the dosing instructions for the form you are using.

Swallow the extended-release capsule whole. Do not crush, break, or chew it.

Take the disintegrating tablet with or without food. Make sure your hands are dry before touching the tablet. Place the tablet on the top of your tongue right after removing it from the bottle. It should melt quickly. After the tablet has melted, swallow or take a sip of water.

Swallow the tablet whole. Do not crush, break, or chew it.

Carefully follow your doctor's instructions for a reduced-calorie diet plan and regular exercise. Talk with your doctor before starting an exercise program.

To avoid trouble with sleeping, take the last dose of the day about 4 to 6 hours before bedtime, unless your doctor tells you otherwise.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For treatment of obesity: For oral dosage form (capsules): Adults and children 17 years of age and older—15 to 30 milligrams (mg) once a day, taken at approximately 2 hours after breakfast. Children 16 years of age and younger—Use is not recommended. For oral dosage form (disintegrating tablets): Adults and children 17 years of age and older—One tablet once a day, taken in the morning. Children 16 years of age and younger—Use is not recommended. For oral dosage form (extended-release capsules): Adults and children 16 years of age and older—One capsule once a day, taken before breakfast or 10 to 14 hours before sleeping. Children 15 years of age and younger—Use is not recommended. For oral dosage form (tablets): Adults and children 17 years of age and older— Lomaira™: One tablet three times a day, taken 30 minutes before meals. Phentermine: 18.75 to 37.5 milligrams (mg) once a day, taken before breakfast or 1 to 2 hours after breakfast. Children 16 years of age and younger—Use is not recommended.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

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