What are the brand names for phentermine 30mg capsules?

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Brand Names for Phentermine 30mg Capsules

Adipex-P is the primary brand name for phentermine 30mg capsules in the United States. 1

Available Formulations

Phentermine is an adrenergic agonist medication approved for short-term weight management and is available in several formulations:

  • Brand name options:

    • Adipex-P (most common brand for 30mg capsules)
    • Lomaira (lower dose tablets - 8mg)
  • Formulation types: 1

    • Capsules (30mg, 37.5mg)
    • Tablets (8mg, 37.5mg)
    • Powder (for compounding)

Dosing Information

The FDA-approved dosing for phentermine includes:

  • Standard dosing: 15-37.5mg once daily 1
  • Common starting dose: 30mg once daily (capsule form)
  • Alternative dosing strategies: 1
    • Quarter tablet (9.375mg)
    • Half tablet (18.75mg)
    • Split dosing (half tablet twice daily)

Clinical Considerations

Efficacy

Phentermine demonstrates significant efficacy for weight loss:

  • Produces approximately 5.1% weight loss at 28 weeks compared to placebo 1
  • In clinical studies, 30mg daily dosing has shown to be more effective than 15mg daily in the first 3 months of treatment 2

Duration of Treatment

  • FDA approval: Short-term use only (≤12 weeks) 1, 3
  • Important caveat: Many providers prescribe phentermine for longer durations as off-label therapy for continued weight management 1

Safety Considerations

Contraindications: 1, 3

  • Cardiovascular disease
  • Uncontrolled hypertension
  • Hyperthyroidism
  • Glaucoma
  • Agitated states
  • History of drug abuse
  • Pregnancy or nursing
  • During or within 14 days of MAOI use
  • Concomitant use with other sympathomimetic amines

Common side effects: 1, 3

  • Dry mouth
  • Insomnia
  • Dizziness
  • Irritability
  • Nausea/vomiting
  • Constipation
  • Elevated heart rate and blood pressure

Monitoring Recommendations

For patients prescribed phentermine 30mg capsules:

  • Assess efficacy and safety monthly for the first 3 months, then at least every 3 months 1
  • Monitor blood pressure and heart rate at each visit 3
  • Consider discontinuation if less than 5% weight loss at 12 weeks 1
  • Be vigilant for potential drug-drug interactions, particularly with serotonergic medications 4

Important Prescribing Considerations

  • Phentermine is a Schedule IV controlled substance 1
  • Should be taken early in the day to minimize insomnia 3
  • Should be used as an adjunct to lifestyle modifications, not as monotherapy 1
  • When discontinuing, consider gradual tapering rather than abrupt cessation 3

Phentermine 30mg capsules should be prescribed with caution and with appropriate monitoring, particularly given its sympathomimetic properties and potential for cardiovascular effects.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Three- and six-month efficacy and safety of phentermine in a Mexican obese population.

International journal of clinical pharmacology and therapeutics, 2021

Guideline

Medication Safety Guidelines

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Potential drug-drug interactions with phentermine among long-term phentermine consumers: A retrospective analysis.

South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 2023

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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