Qsymia is a weight loss pill that contains a combination of topiramate and phentermine. It is used as an adjunct to diet and exercise for the management of weight loss in obese patients.
Qsymia (Phentermine and topiramate) Uses:
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Weight management:
- In patients with a body mass index (BMI) of 27 kg/m2 or 30 kg/m2 and at least one weight-related co-morbid condition, such as hypertension, dyslipidemia, or type 2 diabetes, in addition to a reduced-calorie diet and increased physical activity.
-
Off Label Use of Phentermine and topiramate in Adults:
- Managing one's weight in type 2 diabetes
Qsymia (Phentermine and topiramate) Dose in Adults
Qsymia Dose in Weight management:
- Oral: Initial:
- 14 days of using phentermine 3.75 mg/topiramate 23 mg once daily.
- For 12 weeks, up the dose to phentermine 7.5 mg/topiramate 46 mg once daily, and then assess the effectiveness in terms of weight loss.
- If 3% of your starting weight has not been lost, stop taking the medication or raise the dose to 11.25 mg/69 mg of topiramate once daily for 14 days, and then to 15 mg/92 mg once daily.
- Observe weight loss after 3 months on phentermine 15 mg/topiramate 92 mg; if 5% of baseline body weight has not been lost at a dose of phentermine 15 mg/topiramate 92 mg, then gradually discontinue therapy (e.g, 1 dose every other day for at least 7 days).
Qsymia Dose in Weight management in type 2 diabetes mellitus (off-label):
- Oral: One dose per day of either phentermine 7.5 mg/topiramate 46 mg or phentermine 15 mg/topiramate 92 mg.
Qsymia use in Children:
Not recommended for use in children.
Pregnancy Risk Factor X
- Pregnant women should not use this combination product.
- Oral cleft risk has been associated with first-trimester exposure (cleft lips with or without cleft palate).
- Refer to the individual monographs for more details.
- A increased risk of unfavourable maternal or foetal outcomes is linked to obesity. Medication for weight reduction therapy is not advised, nevertheless, either at conception or while pregnant.
- Before beginning treatment, all females with the potential to become pregnant should have a negative pregnancy test.
- During treatment, reliable contraception must be utilised.
Use of phentermine or topiramate while breastfeeding
- Breast milk contains topiramate, amphetamines and other substances.
- The manufacturer suggests that you stop breastfeeding or discontinue treatment due to possible adverse effects.
- For more information, refer to the individual monographs.
Qsymia Dose in Kidney Disease:
-
Manufacturer's labeling:
-
CrCl ≥50 mL/minute:
- No dosage change is required.
-
CrCl <50 mL/minute:
- Phentermine 7.5 mg/topiramate 46 mg once daily is the maximum dosage.
-
Dialysis:
- Avoid using
-
-
Alternate dosing (Garvey 2016):
-
CrCl ≥50 mL/minute:
- No dosage change is required.
-
CrCl 30 to 49 mL/minute:
- Phentermine 7.5 mg/topiramate 46 mg once daily is the maximum dosage.
-
CrCl <30 mL/minute:
- Use is not advised.
-
Qsymia Dose in Liver Disease:
-
Mild impairment (Child-Pugh class A):
- No dosage change is required.
-
Moderate impairment (Child-Pugh class B):
- Phentermine 7.5 mg/topiramate 46 mg once daily is the maximum dosage.
-
Severe impairment (Child-Pugh class C):
- Don't use (has not been studied).
Common Side Effects of Qsymia (Phentermine and topiramate):
-
Cardiovascular:
- Increased Heart Rate
-
Central Nervous System:
- Paresthesia
- Headache
- Insomnia
-
Endocrine & Metabolic:
- Decreased Serum Bicarbonate
-
Gastrointestinal:
- Xerostomia
- Constipation
-
Respiratory:
- Upper Respiratory Tract Infection
- Nasopharyngitis
Less Common Side Effects Of Qsymia (Phentermine and Topiramate):
-
Cardiovascular:
- Palpitations
- Chest Discomfort
-
Central Nervous System:
- Dizziness
- Depression
- Anxiety
- Cognitive Dysfunction
- Fatigue
- Hypoesthesia
- Disturbance In Attention
- Irritability
- Oral Paresthesia
-
Dermatologic:
- Alopecia
- Skin Rash
-
Endocrine & Metabolic:
- Decreased Serum Potassium
- Hypokalemia
- Increased Thirst
-
Gastrointestinal:
- Dysgeusia
- Nausea
- Diarrhea
- Gastroesophageal Reflux Disease
- Dyspepsia
- Gastroenteritis
- Decreased Appetite
-
Genitourinary:
- Urinary Tract Infection
- Dysmenorrhea
-
Infection:
- Influenza
-
Neuromuscular & Skeletal:
- Back Pain
- Muscle Spasm
- Musculoskeletal Pain
- Neck Pain
-
Ophthalmic:
- Blurred Vision
- Dry Eye Syndrome
- Eye Pain
-
Renal:
- Increased Serum Creatinine
- Nephrolithiasis
-
Respiratory:
- Sinusitis
- Bronchitis
- Cough
- Pharyngolaryngeal Pain
- Sinus Congestion
- Nasal Congestion
Contraindications to Qsymia (Phentermine and topiramate):
- Hypersensitivity
- hyperthyroidism
- Glaucoma
- When starting MAO inhibitor therapy, use within the first 14 days.
- Pregnancy
Warnings and precautions
-
Cardiovascular effects
- Your heart rate at rest can go up as a result. When you begin or increase the dosage, pay close attention.
- If your resting heart rate continues to rise, reduce or stop using the medication.
-
CNS effects
- Medication use can result in mental illnesses or cognitive dysfunction (mood disorders such as anxiety, depression, and insomnia).
- Rapid titration and higher dosages may play a role in the occurrence of cognitive events, including attention, memory, or language difficulties.
- It is important to counsel patients about tasks that require mental alertness, such as driving or operating machinery.
- Patients with a history or depression may be at greater risk. Dosage reduction or discontinuation may prove necessary.
-
Glaucoma
- Acute myopia and secondary-angle closure glaucoma have been associated with topiramate in both children and adults, typically within one month of treatment. But it might happen at any time.
- Patients with severe ocular pain or visual impairment should be discontinued.
-
Hyperthermia
- Hyperthermia and severe oligohidrosis may be caused by topiramate.
- Extreme caution is required and you should monitor carefully during exercise and exposure to high temperatures.
-
Hypokalemia
- Hypokalemia can result. Use caution when taking hydrochlorothiazide and furosemide together.
-
Hypotension
- Hypotension can be increased in hypertensive patients if weight loss is combined with antihypertensive treatment.
- Pre and post-treatment blood pressure should be monitored. Adjust the antihypertensive treatment as necessary, if necessary.
-
Non-Anion gap Hyperchloremic Metabolic acidosis
- Due to the suppression of carbonic acidase, it may lower serum bicarbonate levels and increase renal bicarbonate loss.
- Patients who have illnesses that increase their chance of developing acidosis, such as diabetes, ketoacidosis, renal disease, severe respiratory difficulties, status epilepticus, or surgery, may be more susceptible.
- Monitor serum electrolytes, bicarbonate, and pH before and during treatment.
- If persistent metabolic acidosis is present, reduce or stop taking the medication.
-
Calculus renal:
- It is linked to the formation of kidney stones.
- Topiramate may increase the likelihood of developing renal stones due to its weak carbonic anhydrase inhibitory property.
- A ketogenic diet or concurrent use of carbonic anhydrase inhibitors may increase the incidence of kidney stones in certain patients.
- The chance of forming stones may be decreased by increasing fluid consumption.
-
Effects on the renal system:
- Serum creatinine may rise as a result of this therapy. After 4–8 weeks, there were peaks in serum creatinine levels.
- Drug use must be stopped in order to reverse short-term alterations in serum creatinine and GFR; long-term effects on renal function are unknown.
- Before and during treatment, serum creatinine should be monitored.
- It might be required to lower or stop your dose if you have persistent increases.
-
Suicidal thoughts:
- A pooled analysis of antiepileptic trials showed an increase in suicidal thoughts and behavior (incidence rate: 0.43 percent for patients who received placebo); the risk was evident as soon as one week after initiation, and continued throughout the trial (most trials were less than 24 weeks).
- Patients who have ever attempted suicide or are currently suicidal should not use this medication.
- Patients should be monitored for any changes in depression, suicidal thoughts, or behavior. If they experience suicidal thinking or behavior discontinue treatment.
-
Diabetes:
- Type 2 Diabetes Mellitus: Use extreme caution
- Dietary limitations, weight loss, and anorexia can all lessen the requirement for diabetes medications like Insul or oral hyperglycemic agents.
- Monitor your blood glucose levels before and during treatment.
-
Hepatic impairment
- Patients with severe hepatic impairment should be cautious. Adjustment of dosage may be necessary.
- Patients with severe hepatic impairment (Child Pugh class C) should be avoided
-
Renal impairment
- Patients with impaired renal function should be cautious. Dosage adjustment may be necessary.
- Dialysis should not be administered to patients who have end-stage renal disease.
Phentermine and topiram: Drug Interaction
|
Alizapride |
CNS depressants may have an enhanced CNS depressant impact. |
|
Alpha-/Beta-Agonists (Indirect-Acting) |
The serum concentration of Alpha-/Beta-Agonists may increase in response to carbonic anhydrase inhibitors (Indirect-Acting). |
|
Amantadine |
Amantadine's serum levels may rise in the presence of carbonic anhydrase inhibitors. |
|
Amifampridine |
Amifampridine may have a stronger neuroexcitatory and/or seizure-potentiating impact when combined with substances with seizure threshold lowering potential. |
|
Amitriptyline |
Amitriptyline's CNS depressive action may be strengthened by topiramate. The active metabolite(s) of amitriptyline's serum concentrations may rise in response to topiramate. Amitriptyline's serum levels may rise in response to topiramate. |
|
Ammonium Chloride |
May lower the level of amphetamines in the blood. This result is probably brought on by amphetamine excretion that is increased in the urine. |
|
Amphetamines |
The excretion of amphetamines may be decreased by carbonic anhydrase inhibitors. |
|
Antacids |
Amphetamine excretion may be reduced. |
|
Anticholinergic Agents |
Topiramate's harmful or toxic effects could be exacerbated. |
|
Antihistamines |
Antihistamines' sedative effects may be lessened by amphetamines. |
|
Antihypertensive Agents |
Amphetamines may reduce an antihypertensive agent's ability to lower blood pressure. |
|
Antipsychotic Agents |
May lessen amphetamines' stimulating effects. |
|
Ascorbic Acid |
May lower the level of amphetamines in the blood. |
|
AtoMOXetine |
Could make sympathomimetics' hypertensive effects stronger. The tachycardic impact of sympathomimetics may be increased by atoMOXetine. |
|
Brexanolone |
CNS Depressants may enhance the CNS depressant effect of Brexanolone. |
|
Brimonidine (Topical) |
May enhance the CNS depressant effect of CNS Depressants. |
|
Bromopride |
May enhance the CNS depressant effect of CNS Depressants. |
|
BuPROPion |
May enhance the neuroexcitatory and/or seizure-potentiating effect of Agents With Seizure Threshold Lowering Potential. |
|
Cannabidiol |
May enhance the CNS depressant effect of CNS Depressants. |
|
Cannabis |
May enhance the CNS depressant effect of CNS Depressants. |
|
Carbonic Anhydrase Inhibitors |
May decrease the excretion of Amphetamines. Exceptions: Brinzolamide; Dorzolamide. |
|
Chlorphenesin Carbamate |
CNS depressants' harmful or toxic effects could be increased. |
|
CNS Depressants |
Other CNS depressants' harmful or toxic effects might be exacerbated. |
|
CYP2D6 Inhibitors (Moderate) |
May raise the level of amphetamines in the blood. |
|
CYP2D6 Inhibitors (Strong) |
May raise the level of amphetamines in the blood. |
|
Dimethindene (Topical) |
CNS depressants may have an enhanced CNS depressant impact. |
|
Doxofylline |
Simpathomimetic drugs may intensify Doxofylline's harmful or hazardous effects. |
|
Doxylamine |
CNS depressants may have an enhanced CNS depressant impact. Management: The producer of the pregnancy-safe drug Diclegis (doxylamine/pyridoxine) particularly advises against combining it with other CNS depressants. |
|
Dronabinol |
CNS depressants may have an enhanced CNS depressant impact. |
|
Esketamine |
Could make CNS stimulants' hypertensive effects more pronounced. |
|
Esketamine |
CNS depressants may have an enhanced CNS depressant impact. |
|
Ethosuximide |
Ethosuximide's therapeutic effects may be lessened by amphetamines. |
|
Flecainide |
Ethosuximide's serum levels may drop when amphetamines are consumed. |
|
Fosphenytoin |
Flecainide's serum levels may rise in response to carbonic anhydrase inhibitors. |
|
Gastrointestinal Acidifying Agents |
Topiramate's serum concentration can drop. Fosphenytoin's serum levels may rise when topiramate is used. |
|
Guanethidine |
May lower the level of amphetamines in the blood. |
|
HydrOXYzine |
Could make sympathomimetics more arrhythmogenic. Guanethidine might make sympathomimetic drugs more hypertensive. |
|
Ioflupane I 123 |
CNS depressants may have an enhanced CNS depressant impact. |
|
Kava Kava |
CNS depressants' harmful or toxic effects could be increased. |
|
Lacosamide |
Antiepileptic drugs (Sodium Channel Blockers) may make lacosamide more harmful or poisonous. Particularly, there may be an increased risk for bradycardia, ventricular tachyarrhythmias, or a longer PR interval. |
|
Lithium |
Topiramate may raise the level of lithium in the blood. |
|
Lofexidine |
CNS depressants may have an enhanced CNS depressant impact. Management: Separate drug interaction monographs go into further detail about the medications indicated as exceptions to this book. |
|
Loop Diuretics |
Topiramate's hypokalemic effects might be strengthened. |
|
Magnesium Sulfate |
CNS depressants may have an enhanced CNS depressant impact. |
|
Memantine |
Memantine's serum levels may rise in response to carbonic anhydrase inhibitors. |
|
MetFORMIN |
Topiramate may intensify MetFORMIN's harmful or hazardous effects. |
|
MetyroSINE |
The sedative effects of metyroSINE may be strengthened by CNS depressants. |
|
Mianserin |
May reduce an anticonvulsant's therapeutic impact. |
|
Minocycline |
CNS depressants may have an enhanced CNS depressant impact. |
|
Mirtazapine |
The CNS depressing action of mirtazapine may be enhanced by CNS depressants. |
|
Multivitamins/Fluoride (with ADE) |
May lower the level of amphetamines in the blood. More precisely, vitamin C, or ascorbic acid, which is present in many multivitamins, may lower amphetamine levels. |
|
Multivitamins/Minerals (with ADEK, Folate, Iron) |
May lower the level of amphetamines in the blood. |
|
Multivitamins/Minerals (with AE, No Iron) |
May lower the level of amphetamines in the blood. Specifically, vitamin C may make it harder for amphetamines to be absorbed. |
|
Nabilone |
CNS depressants may have an enhanced CNS depressant impact. |
|
Orlistat |
Could lower the serum level of anticonvulsants. |
|
PHENobarbital |
PHENobarbital's serum levels may be lowered by amphetamines. |
|
Phenytoin |
Topiramate may raise the level of phenytoin in the blood. Topiramate's serum levels may drop if you take phenytoin. |
|
Pioglitazone |
Pioglitazone's serum levels may drop when topiramate is used. |
|
Piribedil |
.Piribedil's CNS depressing impact may be amplified by CNS depressants. |
|
Pramipexole |
The sedative effects of pramipexole might be enhanced by CNS depressants. |
|
Primidone |
Primidone's harmful or poisonous effects may be exacerbated by carbonic anhydrase inhibitors. Specifically, rickets and osteomalacia. Primidone serum levels may be decreased by carbonic anhydrase inhibitors. |
|
QuiNIDine |
QuiNIDine excretion might be decreased by carbonic anhydrase inhibitors. |
|
ROPINIRole |
The sedative effects of CNS depressants may increase those of ROPINIRole. |
|
Rotigotine |
Rotigotine's sedative effects may be boosted by CNS depressants. |
|
Rufinamide |
CNS depressants' harmful or toxic effects could be increased. Particularly, drowsiness and lightheadedness could be worsened. |
|
Selective Serotonin Reuptake Inhibitors |
Selective serotonin reuptake inhibitors may have a worsened or more hazardous effect when taken with CNS depressants. Particularly, there may be an increased risk of psychomotor impairment. |
|
Solriamfetol |
Sympathomimetics may enhance the hypertensive effect of Solriamfetol. |
|
Solriamfetol |
CNS Stimulants may enhance the hypertensive effect of Solriamfetol. |
|
Sympathomimetics |
May enhance the adverse/toxic effect of other Sympathomimetics. |
|
Tedizolid |
May enhance the hypertensive effect of Sympathomimetics. Tedizolid may enhance the tachycardic effect of Sympathomimetics. |
|
Tetrahydrocannabinol |
May enhance the CNS depressant effect of CNS Depressants. |
|
Tetrahydrocannabinol and Cannabidiol |
CNS depressants may have an enhanced CNS depressant impact. |
|
Trimeprazine |
CNS depressants may have an enhanced CNS depressant impact. |
|
Urinary Acidifying Agents |
May lower the level of amphetamines in the blood. |
|
Valproate Products |
Topiramate may intensify the harmful or hazardous effects of products containing valproate. |
|
Risk Factor D (Consider therapy modification) |
|
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Alkalinizing Agents |
Amphetamine excretion may be reduced. Management: Take into account substitutes for the combination of amphetamines and alkalinizing agents. If these medications must be used concurrently, patients should be closely watched for any adverse effects from amphetamine usage. |
|
Blonanserin |
CNS Depressants may enhance the CNS depressant effect of Blonanserin. |
|
Buprenorphine |
CNS Depressants may enhance the CNS depressant effect of Buprenorphine. Management: Consider reduced doses of other CNS depressants, and avoiding such drugs in patients at high risk of buprenorphine overuse/self-injection. Initiate buprenorphine at lower doses in patients already receiving CNS depressants. |
|
CarBAMazepine |
May decrease the serum concentration of Topiramate. |
|
Chlormethiazole |
May enhance the CNS depressant effect of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. |
|
Cocaine (Topical) |
Could make sympathomimetics' hypertensive effects stronger. Management: Whenever possible, look at alternatives to using this combo. When used concurrently, keep a close eye out for noticeably elevated blood pressure or heart rate as well as any signs of myocardial ischemia. |
|
Droperidol |
May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (eg, opioids, barbiturates) with concomitant use. Exceptions to this monograph are discussed in further detail in separate drug interaction monographs. |
|
Estrogen Derivatives (Contraceptive) |
The serum levels of estrogen derivatives may drop while taking topiramate (Contraceptive). Failure with contraception is possible. Management: Risk seems to be greatest at dosages of 200 mg or more of topiramate per day. The usefulness of utilising at least 50 mcg/day of ethinyl estradiol has been suggested, but this is debatable. Think about a nonhormonal method of birth control. |
|
Flunitrazepam |
CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. |
|
HYDROcodone |
CNS Depressants may enhance the CNS depressant effect of HYDROcodone. Management: Avoid concomitant use of hydrocodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. |
|
Iohexol |
Agents With Seizure Threshold Lowering Potential may enhance the adverse/toxic effect of Iohexol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iohexol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic anticonvulsants. |
|
Iomeprol |
Agents With Seizure Threshold Lowering Potential may enhance the adverse/toxic effect of Iomeprol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iomeprol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic anticonvulsants. |
|
Iopamidol |
Agents With Seizure Threshold Lowering Potential may enhance the adverse/toxic effect of Iopamidol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iopamidol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic anticonvulsants. |
|
Linezolid |
Could make sympathomimetics' hypertensive effects stronger. Reduce the first doses of sympathomimetic drugs and closely monitor individuals on linezolid for an augmented pressor response. There are currently no suggestions for specific dose adjustments. |
|
Mefloquine |
May reduce an anticonvulsant's therapeutic impact. Anticonvulsant serum concentrations may be reduced by mefloquine. Treatment: Mefloquine should not be used to prevent malaria in those who have a history of convulsions. With concurrent use, closely monitor anticonvulsant concentrations and therapeutic response. |
|
Methenamine |
The therapeutic effects of methenamine may be diminished by carbonic anhydrase inhibitors. Management: Take into account avoiding this pairing. If you use a carbonic anhydrase inhibitor at the same time as methenamine, keep an eye out for any diminished therapeutic effects. |
|
Methotrimeprazine |
CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. |
|
Opioid Agonists |
CNS Depressants may enhance the CNS depressant effect of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. |
|
OxyCODONE |
CNS Depressants may enhance the CNS depressant effect of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. |
|
Perampanel |
May enhance the CNS depressant effect of CNS Depressants. Management: Patients taking perampanel with any other drug that has CNS depressant activities should avoid complex and high-risk activities, particularly those such as driving that require alertness and coordination, until they have experience using the combination. |
|
Progestins (Contraceptive) |
Progestin levels in the serum may drop while taking topiramate (Contraceptive). Treatment: Inform patients that this combination may result in decreased contraceptive efficacy. Think about including an additional (non-hormonal) type of birth control. |
|
Salicylates |
Could intensify the hazardous or harmful effects of carbonic anhydrase inhibitors. This identical combination may increase salicylate toxicity. Management: Whenever you can, stay away from these pairings. Use of dichlorphenamide with aspirin at high doses is not advised. If a different combination is used, patients should be closely watched for side effects. There have been reports of tachypnea, anorexia, lethargy, and coma. |
|
Sodium Oxybate |
CNS depressants may have an enhanced CNS depressant impact. Management: Take into account substitutes for combined use. Reduce the doses of one or more medications when simultaneous use is necessary. It is not advised to use sodium oxybate with alcoholic beverages or hypnotic sedatives. |
|
Suvorexant |
Suvorexant's CNS depressing effects may be amplified by other CNS depressants. Treatment: Suvorexant and/or any other CNS depressant dosage reduction may be required. Suvorexant shouldn't be taken with alcohol, and it shouldn't be taken for sleeplessness with any other medication either. |
|
Tapentadol |
CNS depressants may have an enhanced CNS depressant impact. Treatment: When feasible, refrain from using tapentadol and benzodiazepines or other CNS depressants simultaneously. Only in the event that other treatment choices are insufficient should these medications be combined. Limit the duration and dosage of each medicine when used together. |
|
Thiazide and Thiazide-Like Diuretics |
Topiramate's hypokalemic effects might be strengthened. The blood concentration of topiramate may rise in response to thiazide and thiazide-like diuretics. When using a thiazide diuretic, monitor for elevated topiramate levels and any negative consequences (such as hypokalemia). |
|
Zolpidem |
CNS Depressants may enhance the CNS depressant effect of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. |
|
Risk Factor X (Avoid combination) |
|
|
Acebrophylline |
Could make CNS stimulants more stimulating. |
|
Alcohol (Ethyl) |
May intensify topiramate's CNS depressive effects. The blood content of topiramate may rise by drinking alcohol (Ethyl). Use with the extended-release topiramate capsules only, please (Trokendi XR). Additionally, in the later part of the dose interval, topiramate concentrations may be below therapeutic levels. Treatment: It is not advised to consume alcohol concurrently within six hours after taking Trokendi XR, an extended-release topiramate. Topiramate should never be combined with alcohol, and if it must be, only with the utmost caution. |
|
Azelastine (Nasal |
CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). |
|
Bromperidol |
May enhance the CNS depressant effect of CNS Depressants. |
|
Carbonic Anhydrase Inhibitors |
The negative or hazardous effects of other carbonic anhydrase inhibitors might be heightened. There have been reports of acid-base abnormalities developing when oral and ophthalmic carbonic anhydrase inhibitors are used simultaneously. Avoid using multiple carbonic anhydrase inhibitors at the same time. |
|
Iobenguane Radiopharmaceutical Products |
Iobenguane radiopharmaceutical products' therapeutic effects may be reduced by amphetamines. Treatment: Before administering iobenguane, stop taking any medications that could impede or interfere with catecholamine transport or uptake for at least five biological half-lives. After each dose of iobenguane, wait at least 7 days before administering these medications. |
|
Iobenguane Radiopharmaceutical Products |
CNS Iobenguane radiopharmaceutical products' therapeutic effects may be reduced by stimulants. Treatment: Before administering iobenguane, stop taking any medications that could impede or interfere with catecholamine transport or uptake for at least five biological half-lives. After each dose of iobenguane, wait at least 7 days before administering these medications. |
|
Monoamine Oxidase Inhibitors |
Amphetamines' ability to cause hypertension may be increased. However, unlike other monoamine oxidase inhibitors, linezolid and tedizolid have different management recommendations. |
|
Orphenadrine |
The CNS depressing action of orphenadrine may be enhanced by CNS depressants. |
|
Oxomemazine |
May enhance the CNS depressant effect of CNS Depressants. |
|
Paraldehyde |
CNS Depressants may enhance the CNS depressant effect of Paraldehyde. |
|
Sibutramine |
May enhance the adverse/toxic effect of Centrally Acting Weight Loss Agents. |
|
Thalidomide |
The CNS depressing effect of thalidomide may be enhanced by CNS depressants. |
|
Ulipristal |
Ulipristal's serum levels may drop when topiramate is used. |
Monitoring Parameters:
- Weight;
- resting heart rate;
- serum bicarbonate,
- potassium,
- glucose,
- blood pressure;
- suicidality
- angle closure glaucoma;
- acidosis
How to administer Qsymia (Phentermine and topiramate)?
- Administer in the morning without regard to meals;
- avoid late evening administration (potential for insomnia).
Mechanism of action of Qsymia (Phentermine and topiramate):
Phentermine
- Sympathetic amine that has similar pharmacologic properties to amphetamines.
- CNS effects are what appear to play a secondary role in the mechanism that reduces appetite.
- Its benefits on weight loss are brought about by its augmentation of satiety and suppression of hunger. Based on a number of plausible mechanisms, this.
- It slightly inhibits carbonic anhydrase, potentiates GABA(A), inhibits AMPA/kainite glutamate receivers, and blocks voltage-dependent sodium channels in neurons.
You can contact individual agents ( Topiramate, Phenteramine).
International Brands of Phentermine and topiramate:
- Qsymia
Phentermine and topiramate Brand Names in Pakistan:
No Brands Available in Pakistan. Topiramate is available but the combination pill is not available.
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