Phentermine 20mg | Bupropion 65mg | Methylcobalamin 1mg | Naltrexone 8mg | Topiramate 15mg

Route: Oral capsule.

• Take once daily in the morning with or without food. Avoid evening dosing to prevent insomnia (phentermine and bupropion are activating).
• Swallow the capsule whole with a full glass of water. Do not crush or open.
• Consistent daily timing supports stable plasma levels and tolerability.

All dosing is prescriber-determined. This formulation represents a specific patient-directed dosage. General principles based on individual ingredient evidence:

• Bupropion + naltrexone synergy: the naltrexone component blocks opioid-mediated auto-inhibition of POMC neurons, amplifying bupropion's anorexigenic effect—a mechanism analogous to the FDA-approved Contrave combination.
• Phentermine + topiramate: aligned with components of the FDA-approved Qsymia, with phentermine doses typically ranging 3.75–15 mg and topiramate 23–92 mg in the approved product.
• Prescribers typically initiate at lower doses and titrate based on response, tolerability, and weight-loss targets (≥3% body weight at 12 weeks is a standard response threshold).
• Topiramate should be tapered if discontinuation is needed to reduce seizure risk.
• Methylcobalamin 1 mg daily is a supplemental dose; no titration required.

• Phentermine: Acts as a TAAR1 agonist triggering norepinephrine (and to a lesser extent dopamine) release in the hypothalamic lateral nucleus, directly suppressing appetite and producing mild thermogenesis.
• Bupropion: Inhibits reuptake of norepinephrine and dopamine; in the arcuate nucleus, stimulates POMC neurons to release alpha-MSH, activating melanocortin-4 receptors (MC4R) to reduce food intake and increase energy expenditure.
• Naltrexone: Blocks mu-opioid receptors on POMC cells, preventing beta-endorphin from auto-inhibiting POMC neurons; this sustains and amplifies bupropion's activation of the POMC/MC4R satiety pathway.
• Topiramate: Potentiates GABA-A receptor activity, inhibits AMPA/kainate glutamate receptors, weakly inhibits carbonic anhydrase—collectively dampening reward-related appetite signals and prolonging feelings of satiety.
• Methylcobalamin: Serves as a cofactor for methionine synthase and methylmalonyl-CoA mutase; supports myelin integrity and neurological function, which may be compromised during prolonged caloric restriction or metformin co-therapy.

Indication context: Prescribers may consider this preparation for adults with obesity (BMI ≥30 kg/m²) or overweight (BMI ≥27 kg/m²) with at least one weight-related comorbidity (hypertension, type 2 diabetes, dyslipidemia), as an adjunct to reduced-calorie diet and increased physical activity. This multi-mechanism approach extrapolates from established data on Qsymia (phentermine/topiramate) and Contrave (bupropion/naltrexone).

Monitoring considerations:

• Body weight and BMI at each visit; assess ≥3% weight loss at 12 weeks to determine continued utility.
• Blood pressure and heart rate (phentermine has sympathomimetic effects).
• Blood glucose in diabetic patients (improved insulin sensitivity from weight loss may require dose adjustments of diabetes medications).
• Serum bicarbonate (topiramate's carbonic anhydrase inhibition can cause metabolic acidosis).
• Mental health: Screen for mood changes, suicidal ideation (bupropion warning), and seizure history.
• Pregnancy testing (monthly) due to topiramate's teratogenicity (cleft palate risk); ensure effective contraception.

Contraindications:

• Concurrent or recent (within 14 days) use of MAOIs (due to phentermine and bupropion).
• Pregnancy (topiramate is teratogenic; phentermine Pregnancy Category X).
• Uncontrolled hypertension, hyperthyroidism, or glaucoma (phentermine).
• Known hypersensitivity to any component.
• Seizure disorder history (bupropion lowers seizure threshold).
• Active eating disorder (anorexia nervosa or bulimia; bupropion contraindicated).

Warnings & Precautions:

• Increased heart rate and blood pressure with phentermine; assess cardiovascular risk before prescribing.
• Cognitive impairment, word-finding difficulty, paresthesias with topiramate (dose-related).
• Acute angle-closure glaucoma and visual disturbances with topiramate—discontinue immediately if acute visual symptoms occur.
• Decreased sweating and hyperthermia with topiramate; ensure adequate hydration in warm environments.
• Nephrolithiasis risk with topiramate; encourage high fluid intake.
• Phentermine has abuse potential (Schedule IV controlled substance); use with caution in patients with substance use disorder.

Drug Interactions:

• MAOIs: absolute contraindication with both phentermine and bupropion.
• Other dopaminergic agents (e.g., levodopa, amantadine): may enhance bupropion side effects.
• Oral contraceptives: topiramate may reduce efficacy; advise non-hormonal contraception.
• Antihypertensives: phentermine may reduce efficacy by increasing sympathetic tone.
• Opioid medications: naltrexone will block opioid analgesia; do not use in patients requiring opioids.

Common Side Effects: Dry mouth, constipation, insomnia, paresthesias (topiramate), altered taste, decreased appetite; less commonly, headache, dizziness, tachycardia.

Store at room temperature (15–30°C / 59–86°F). Keep in the dispensing container, tightly capped, away from moisture and heat. Do not freeze. Keep out of reach of children. Phentermine is a federally controlled substance (CIV); store securely. Use within the beyond-use date assigned by Genesis Compounding.

Why are five medications in one capsule?

Each ingredient targets a different pathway controlling appetite, food reward, and energy balance. The combination is designed to produce additive or synergistic effects—e.g., naltrexone amplifies bupropion's hypothalamic effect; phentermine and topiramate act via complementary anorexigenic mechanisms—potentially achieving greater and more sustained weight loss than any single agent alone.

Why is methylcobalamin included?

Methylcobalamin (active vitamin B12) is included to support neurological health and prevent deficiency that can occur during significant caloric restriction. It also supports healthy homocysteine metabolism. This component adds nutritional support to the weight management regimen.

Is this the same as Qsymia or Contrave?

This compounded formulation contains the same classes of active ingredients found in Qsymia (phentermine + topiramate) and Contrave (bupropion + naltrexone), but at different doses and combined in a single capsule. This multi-ingredient combination capsule is not FDA-approved; it is prepared by Genesis Compounding as a patient-specific 503A preparation under prescriber direction.

Are there risks with alcohol while taking this medication?

Alcohol should be avoided or strictly minimized. Bupropion may lower the seizure threshold, and this risk is increased by alcohol. Naltrexone may cause nausea and is incompatible with opioid analgesics. Your prescriber will review these precautions with you.

What pregnancy precautions are necessary?

Topiramate is teratogenic (associated with cleft palate) and phentermine is Pregnancy Category X. Women of childbearing potential must use effective non-hormonal contraception (oral contraceptives may be less effective with topiramate) and undergo monthly pregnancy testing. Discontinue immediately if pregnancy occurs.