Before Using

Drug information provided by: IBM Micromedex

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of phentermine and topiramate combination in children younger than 12 years of age. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of phentermine and topiramate combination in the elderly. However, elderly patients are more likely to have kidney, liver, or heart problems, which may require caution and an adjustment in the dose for patients receiving phentermine and topiramate combination.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

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

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

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

  • Acetazolamide
  • Alfentanil
  • Alprazolam
  • Benzhydrocodone
  • Brinzolamide
  • Bromazepam
  • Buprenorphine
  • Butorphanol
  • Calcifediol
  • Calcium Oxybate
  • Cannabidiol
  • Carbinoxamine
  • Cetirizine
  • Citalopram
  • Clobazam
  • Clonazepam
  • Codeine
  • Daridorexant
  • Desogestrel
  • Dexmedetomidine
  • Dichlorphenamide
  • Dienogest
  • Dihydrocodeine
  • Dorzolamide
  • Doxylamine
  • Drospirenone
  • Esketamine
  • Estradiol
  • Ethinyl Estradiol
  • Ethynodiol
  • Etonogestrel
  • Fentanyl
  • Flibanserin
  • Gabapentin
  • Gabapentin Enacarbil
  • Gestodene
  • Hydrocodone
  • Hydromorphone
  • Iobenguane I 131
  • Ketamine
  • Lemborexant
  • Levocetirizine
  • Levonorgestrel
  • Levorphanol
  • Lofexidine
  • Loxapine
  • Magnesium Oxybate
  • Medroxyprogesterone
  • Meperidine
  • Mestranol
  • Methadone
  • Methazolamide
  • Metoclopramide
  • Midazolam
  • Morphine
  • Morphine Sulfate Liposome
  • Nalbuphine
  • Nifedipine
  • Nomegestrol
  • Norelgestromin
  • Norethindrone
  • Norgestimate
  • Norgestrel
  • Orlistat
  • Oxycodone
  • Oxymorphone
  • Pentazocine
  • Periciazine
  • Piperaquine
  • Potassium Oxybate
  • Pregabalin
  • Remifentanil
  • Remimazolam
  • Ropeginterferon Alfa-2b-njft
  • Scopolamine
  • Segesterone
  • Sodium Oxybate
  • Sufentanil
  • Tapentadol
  • Tramadol
  • Trazodone
  • Ulipristal
  • Zolpidem

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Carbamazepine
  • Fosphenytoin
  • Ginkgo
  • Hydrochlorothiazide
  • Phenobarbital
  • Phenytoin
  • Pioglitazone
  • Posaconazole
  • Valproic Acid

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of 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, change some of the other medicines you take, or give you special instructions about the use of food, alcohol, or tobacco.

  • Ethanol

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Allergy to aspirin—Use with caution. This medicine contains a yellow dye called tartrazine, which may cause allergic reactions (eg, asthma) in patients with this condition.
  • Allergy to similar medicines (eg, adrenaline, amphetamine, dopamine, dobutamine, ephedrine, or lisdexamfetamine) or
  • Glaucoma or
  • Hyperthyroidism (overactive thyroid) or
  • Kidney disease on dialysis, end stage or
  • Liver disease, severe—Should not be used in patients with these conditions.
  • Bone problems (eg, osteoporosis) or
  • Depression, history of or
  • Drug abuse or dependence, history of or
  • Eye or vision problems or
  • Hypokalemia (low potassium in the blood) or
  • Kidney stones, history of or
  • Mental illness, history of or
  • Metabolic acidosis (too much acid in the blood), history of or
  • Seizures or epilepsy, history of—Use with caution. May make these conditions worse.
  • Diarrhea or
  • Ketogenic diet (high-fat, low-protein, low-carbohydrate diet) or
  • Kidney problems or
  • Lung disease or other breathing problems or
  • Surgery—These problems may make a condition called metabolic acidosis occur or make it worse.
  • Heart or blood vessel disease, unstable—Use is not recommended in patients with these conditions.
  • Kidney disease, moderate or severe or
  • Liver disease, moderate—Use with caution. The effects may be increased because of slower removal of the medicine from the body.

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