What is Phentermine: Uses, Warnings & Interactions

Your doctor will tell you how much medicine to use. Do not use more than directed.

Take the 37.5 mg tablet or capsule before breakfast or one to two hours after breakfast.

• Swallow the tablet or capsule whole with a glass of water.

Take the Lomaira tablet (8 mg tablet) three times per day 30 minutes before a meal.

• Swallow the tablet whole with a glass of water.

• Lomaira tablets are scored so that they can be divided into two 4 mg doses. Ask the healthcare provider or pharmacist how to divide tablets if you are prescribed a lower dose.

• Avoid taking Lomaira tablets late in the evening because the dose could interfere with sleep.

The orally disintegrating tablets are taken in the morning with or without food.

• Remove the orally disintegrating tablet gently from the bottle with dry hands.

• Place the tablet immediately on the tongue.

• Allow it to completely dissolve on the tongue.

• Then swallow with or without a glass of water.

Swallow the tablet whole with a drink of water.

Store phentermine tablets or capsules in a closed container at room temperature out of the reach of children.

Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. 

Do not take extra medicine to make up for a missed dose.

This medicine is not right for everyone. 

Do not take phentermine if you have had an allergic reaction to phentermine or similar medicines.

Do not take phentermine if you have:

• A history of cardiovascular disease including uncontrolled high blood pressure

• Overactive thyroid

• Glaucoma

• Agitated states

• End-stage kidney disease

• A history of drug abuse

Do not take phentermine if you are pregnant or breastfeeding.

It is not safe to take this medicine during pregnancy. Weight loss could harm an unborn baby. Tell your doctor right away if you become pregnant.

Do not breastfeed when taking phentermine.

This medicine is not for long-term use.

Tell any doctor or other healthcare provider who treats you that you are using this medicine.

Your doctor may do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

Phentermine is a controlled substance because of its risk of physical dependence, misuse, overdose, and theft.

• Do not use phentermine for longer than a few weeks.

• Do not use more than the prescribed dose.

• Giving phentermine to another person is against the law.

• Store this medicine out of the reach of children and other people.

Tell your doctor if you have:

• Kidney disease

• Diabetes

• Glaucoma

• Congestive heart failure

• Heart or blood vessel disease

• Heart valve problems

• A history of stroke

• High blood pressure

• Overactive thyroid

• Problems with agitation

• A history of drug abuse

This medicine may cause the following problems:

• Primary pulmonary hypertension (a serious lung problem)

• Heart valve disease

• Increase in blood pressure

• Changes in blood sugar levels

This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.

To avoid potentially hazardous drug interactions, tell the prescribing healthcare provider about all prescription drugs, over-the-counter medicines, and supplements you are using before taking atorvastatin.

Tell other healthcare providers you are using this medicine before they prescribe new medications.

Do not use this medicine and an MAO inhibitor (MAOI) within 14 days of each other.

When taking phentermine, avoid other weight loss drugs or remedies unless cleared by the doctor. This not only includes weight loss drugs purchased with or without a prescription, but weight loss supplements and herbal products, as well. 

It may not be safe to take phentermine with SSRIs or amphetamines.

Phentermine can decrease the effectiveness of insulin and other diabetes medications, so dosages may need to be adjusted when phentermine is being used.

Do not drink alcohol while you are using this medicine.