Home Drug Guide Phenmetrazine Hydrochloride

Drug Guide

Generic Name

Phenmetrazine Hydrochloride

Brand Names Preludin

Classification

Therapeutic: Appetite Suppressant / Stimulant

Pharmacological: Amphetamine-like Stimulant

FDA Approved Indications

  • Short-term treatment of obesity as an appetite suppressant

Mechanism of Action

Phenmetrazine is a central nervous system stimulant that releases catecholamines (dopamine and norepinephrine) and inhibits their reuptake, leading to increased sympathetic activity which suppresses appetite.

Dosage and Administration

Adult: Typically 25-50 mg orally two to three times daily before meals. Dose may be adjusted based on response and tolerability.

Pediatric: Not approved for pediatric use.

Geriatric: Use with caution, start at lower end of dosage range due to increased sensitivity and comorbidities.

Renal Impairment: Use cautiously; dose adjustment may be necessary.

Hepatic Impairment: Use cautiously; monitor closely. Specific dosage adjustments are not well established.

Pharmacokinetics

Absorption: Rapidly absorbed from gastrointestinal tract.

Distribution: Widely distributed, crosses the blood-brain barrier.

Metabolism: Metabolized minimally; primarily excreted unchanged in urine.

Excretion: Mostly via renal excretion, with a half-life of approximately 4-7 hours.

Half Life: Approximately 4-7 hours.

Contraindications

  • History of cardiovascular disease, hypertension, hyperthyroidism, glaucoma, drug abuse or dependence, MAOI use within 14 days.
  • Known hypersensitivity to phenmetrazine.

Precautions

  • Use cautiously in patients with psychiatric disorders, history of substance abuse, or underlying medical conditions affecting cardiovascular status. Risk of dependence and abuse is significant.

Adverse Reactions - Common

  • Insomnia (Frequent)
  • Dry mouth (Frequent)
  • Restlessness (Frequent)
  • Elevated blood pressure (Frequent)

Adverse Reactions - Serious

  • Hypertensive crisis (Rare)
  • Psychosis or hallucinations (Rare)
  • Dependence or addiction (Serious risk)

Drug-Drug Interactions

  • MAOIs: risk of hypertensive crisis
  • Other stimulants: additive effects
  • Antihypertensives: may diminish effect

Drug-Food Interactions

  • Avoid caffeine and other stimulants

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood pressure, heart rate, mental status, signs of abuse or dependence.

Diagnoses:

  • Risk for hypertension
  • Impaired sleep pattern
  • Risk for substance dependence

Implementation: Administer as prescribed, monitor vital signs and mental status regularly.

Evaluation: Assess effectiveness in appetite suppression, monitor for adverse reactions or signs of misuse.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Avoid caffeine and other stimulants.
  • Report any chest pain, palpitations, or mental changes.
  • Do not abruptly discontinue medication to avoid withdrawal symptoms.

Special Considerations

Black Box Warnings:

  • Potential for abuse and dependence.
  • Risk of serious cardiovascular events, including sudden death, stroke, and heart attack, especially in patients with underlying cardiovascular disease.

Genetic Factors: None established.

Lab Test Interference: May affect measurements of certain laboratory tests related to catecholamine levels.

Overdose Management

Signs/Symptoms: Severe hypertension, hyperthermia, agitation, confusion, hallucinations, seizures, cardiac arrhythmias.

Treatment: Supportive care, control of blood pressure, cooling measures for hyperthermia, benzodiazepines for agitation or seizures, activated charcoal if ingestion is recent.

Storage and Handling

Storage: Store at room temperature away from light and moisture.

Stability: Stable when stored properly, expiry date should be checked.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.