Home Drug Guide Chloroquine Hydrochloride

Drug Guide

Generic Name

Chloroquine Hydrochloride

Brand Names Aralen Hydrochloride

Classification

Therapeutic: Antimalarial agent

Pharmacological: Aminoquinoline antimalarial

FDA Approved Indications

  • Prophylaxis of malaria
  • Treatment of uncomplicated Plasmodium vivax, P. ovale, P. malariae, and sensitive strains of P. falciparum malaria

Mechanism of Action

Chloroquine accumulates in the parasite's food vacuoles, inhibiting heme polymerization, leading to accumulation of toxic heme, which destroys the parasite.

Dosage and Administration

Adult: For malaria prophylaxis: 500 mg chloroquine base (equivalent to 620 mg chloroquine phosphate) once weekly starting 1-2 weeks before travel, continuing during travel and for 4-6 weeks after leaving endemic area. For treatment: 600 mg base (750 mg phosphate) initially, then 300 mg base (375 mg phosphate) at 6, 24, and 48 hours.

Pediatric: Dosage varies with weight and age; typically, 10 mg/kg chloroquine base (12.5 mg/kg phosphate) for the initial dose, then 5 mg/kg (6.25 mg/kg phosphate) at 6, 24, and 48 hours.

Geriatric: Use with caution; dose adjustments based on renal and hepatic function may be necessary.

Renal Impairment: Adjust dose as necessary; monitor for toxicity.

Hepatic Impairment: Use cautiously due to potential accumulation.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Wide distribution; crosses the placenta and enters breast milk.

Metabolism: Primarily hepatic.

Excretion: Renal and biliary routes.

Half Life: Approximately 1-2 months, due to large volume of distribution.

Contraindications

  • History of hypersensitivity to chloroquine or other 4-aminoquinolines
  • Retinal or visual field changes from previous therapy

Precautions

  • Use cautiously in patients with hepatic or renal impairment, psoriasis, or a history of epilepsy. Monitor ocular health during prolonged use.
  • Pregnancy Category C; benefit-risk assessment needed.

Adverse Reactions - Common

  • Nausea, vomiting, diarrhea (Common)
  • Headache, dizziness (Common)

Adverse Reactions - Serious

  • Retinal toxicity, irreversible visual damage (Rare but serious)
  • Cardiac toxicity, including QT prolongation and arrhythmias (Rare but serious)
  • Seizures, hemolytic anemia in G6PD deficiency (Rare)

Drug-Drug Interactions

  • Coadministration with other drugs that prolong QT interval (e.g., quinidine, amiodarone) increases risk of arrhythmias.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Baseline ocular examination, assessment of renal and hepatic function, G6PD deficiency testing.

Diagnoses:

  • Risk of retinal toxicity
  • Risk of cardiac arrhythmias

Implementation: Monitor for adverse effects, patient education on visual changes, periodic eye exams during prolonged therapy.

Evaluation: Regular ophthalmologic assessments and monitoring for adverse reactions.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Report any visual changes, hearing loss, or unusual side effects immediately.
  • Avoid alcohol and medications that can prolong QT interval unless approved by healthcare provider.

Special Considerations

Black Box Warnings:

  • Potential for irreversible retinal damage; ophthalmologic examinations needed during prolonged therapy.
  • Falciparum malaria may be resistant; confirm susceptibility before use.

Genetic Factors: G6PD deficiency can increase risk of hemolytic anemia.

Lab Test Interference: May interfere with some serologic and blood tests.

Overdose Management

Signs/Symptoms: Nausea, vomiting, visual disturbances, seizures, cardiac arrest.

Treatment: Supportive care; activated charcoal if early; manage seizures and cardiac arrhythmias as per protocols.

Storage and Handling

Storage: Store in a tightly closed container at room temperature (20-25°C), away from moisture and light.

Stability: Stable under proper storage conditions.

🛡️ 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.