Home Drug Guide Primaquine Phosphate

Drug Guide

Generic Name

Primaquine Phosphate

Brand Names Primaquine

Classification

Therapeutic: Antimalarial

Pharmacological: 2-Aminopyridine derivative

FDA Approved Indications

  • Prevention and treatment of relapse of Plasmodium vivax and Plasmodium ovale malaria

Mechanism of Action

Primaquine acts by producing oxidative stress within the parasite, damaging their mitochondria and other cellular components, leading to parasite death. It is effective against the liver (hypnozoite) stages of certain Plasmodium species.

Dosage and Administration

Adult: Usually 15 mg base (26.3 mg phosphate) once daily for 14 days.

Pediatric: Dose based on weight, typically 0.5 mg/kg/day for 14 days.

Geriatric: Adjusted dose depending on renal and hepatic function; caution advised.

Renal Impairment: Use with caution; monitor renal function and consider dosage adjustments.

Hepatic Impairment: Caution recommended; hepatic function should be monitored.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Widely distributed in body tissues, including liver.

Metabolism: Primarily hepatic via CYP2D6 enzymes.

Excretion: Metabolites excreted in urine.

Half Life: Approximately 4-7 hours.

Contraindications

  • G6PD deficiency (risk of hemolysis)
  • Allergy to primaquine

Precautions

  • Use in pregnancy only if benefits outweigh risk, as data is limited.
  • Monitor for hemolytic anemia, especially in G6PD deficiency.

Adverse Reactions - Common

  • Gastrointestinal upset (nausea, vomiting) (Common)
  • Headache (Common)

Adverse Reactions - Serious

  • Hemolytic anemia (in G6PD deficiency) (Serious, risk increases in G6PD deficiency)
  • Leukopenia, thrombocytopenia (Serious, rare)

Drug-Drug Interactions

  • Be cautious with other drugs causing hemolysis or bone marrow suppression, e.g., sulfonamides.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Assess G6PD status before initiation. Monitor hemoglobin, hematocrit, and liver function tests.

Diagnoses:

  • Risk for hemolytic anemia
  • Risk for hepatic injury

Implementation: Administer with food to reduce gastrointestinal upset. Educate patient on importance of adherence to the full course.

Evaluation: Monitor for signs of hemolysis, adverse reactions, and effectiveness of treatment.

Patient/Family Teaching

  • Instruct to complete the full course of therapy.
  • Advise to report any symptoms of anemia (fatigue, weakness, pallor).
  • Warn against use without G6PD testing.
  • Discuss the importance of regular blood tests during therapy.

Special Considerations

Black Box Warnings:

  • Hemolytic anemia in patients with G6PD deficiency.

Genetic Factors: CYP2D6 poor metabolizers may have reduced efficacy.

Lab Test Interference: May interfere with some liver function tests.

Overdose Management

Signs/Symptoms: Hemolytic anemia, gastrointestinal symptoms, dizziness.

Treatment: Supportive care, blood transfusions if necessary, monitor hemoglobin levels, and ensure adequate hydration.

Storage and Handling

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

Stability: Stable under recommended conditions until expiration date.

🛡️ 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.