Chloroquine Medications
Chloroquine is an antimalarial medication that treats and prevents malaria. It is also used for autoimmune conditions like rheumatoid arthritis.
About Chloroquine
Chloroquine is a synthetic 4-aminoquinoline compound that has been used for decades to prevent and treat malaria. It belongs to the antimalarial class and also exhibits immunomodulatory activity, which has led to its inclusion in treatment protocols for certain rheumatic diseases. The drug works by interfering with the parasite’s ability to detoxify heme and by raising the pH of intracellular vesicles, a mechanism that also dampens inflammatory pathways in human immune cells. Commercially, chloroquine has appeared under brand names such as Resochin, Nivaquine and Aralen, while generic tablets are widely manufactured. Although resistance has limited its role in malaria therapy in many regions, chloroquine remains a valuable option for short-term prophylaxis and for specific autoimmune indications where physicians deem it appropriate. Off-label uses, such as adjunctive therapy in certain viral infections, have been explored but are not formally approved.
What is chloroquine?
Chloroquine is classified as a quinoline-type antimalarial. The United States Food and Drug Administration first approved it in 1955 for the treatment of Plasmodium infections, and the World Health Organization incorporated it into its malaria eradication program shortly thereafter. Subsequent regulatory updates have expanded its label to include prophylaxis of Plasmodium vivax and P. falciparum in areas where sensitivity remains. In Singapore, the Health Sciences Authority (HSA) does not list chloroquine as a first-line antimalarial because of widespread drug resistance, but the ingredient may be accessed for approved non-malaria indications through licensed pharmacies. At the molecular level, chloroquine diffuses into the parasite’s acidic food vacuole, where it becomes protonated and accumulates, inhibiting heme polymerization and causing toxic heme buildup. In human cells, the same pH-altering effect impairs antigen processing and reduces cytokine release, accounting for its utility in rheumatoid arthritis and systemic lupus erythematosus. Both branded tablets and generic equivalents are available via our online pharmacy.
How chloroquine works
Mechanism of Action
Chloroquine freely crosses cell membranes and becomes trapped in acidic compartments-namely the malaria parasite’s food vacuole and lysosomal/endosomal spaces of immune cells. Within these organelles it elevates pH, which blocks the conversion of toxic heme into inert hemozoin and disrupts protein degradation pathways. The drug also inhibits Toll-like receptor signaling and reduces the production of interleukin-6, tumor-necrosis factor-α, and other pro-inflammatory cytokines.
Therapeutic Effects
By preventing heme detoxification, chloroquine causes lethal accumulation of free heme within the parasite, halting its replication. In autoimmune contexts, the dampening of cytokine release leads to reduced joint inflammation and lower autoantibody titers, translating into clinical improvement in lupus or rheumatoid arthritis patients.
Onset and Duration
After oral administration, peak plasma concentrations are reached in 2-4 hours. Parasite clearance typically begins within 24 hours, and a single therapeutic course (usually 600 mg followed by 300 mg at 24 h and 48 h) can cure uncomplicated malaria. For prophylaxis, steady-state concentrations are achieved after 2 weeks of daily dosing, providing protection for the duration of exposure. The drug’s elimination half-life ranges from 1 to 2 months, reflecting extensive tissue binding.
Approved Uses and Applications
Approved Indications
- Treatment of uncomplicated Plasmodium falciparum and P. vivax malaria - recommended where local resistance patterns permit. (HSA guidance)
- Malaria chemoprophylaxis for travelers to regions with chloroquine-sensitive strains.
- Rheumatoid arthritis and systemic lupus erythematosus - approved in several countries as an immunomodulatory agent; Singapore physicians may prescribe off-label under specialist supervision.
Off-Label Uses
- Adjunctive therapy for viral infections (e.g., early COVID-19 studies) - research has shown mixed results; the use remains experimental and is not endorsed by regulatory agencies.
- Dermatologic conditions such as cutaneous lupus - supported by small clinical series but lacks formal approval.
Clinical Efficacy
A randomized, double-blind trial published in The Lancet (2006) demonstrated a 96 % cure rate for chloroquine-sensitive malaria with a standard 3-day regimen. In systemic lupus erythematosus, a meta-analysis in Annals of the Rheumatic Diseases (2014) reported a 35 % reduction in disease flares among patients receiving chloroquine compared with placebo. These data underscore the drug’s reliable antimalarial activity and modest but meaningful immunomodulatory benefit.
Buying chloroquine from Our Online Pharmacy
Why Choose Our Service
Access to chloroquine can be limited in Singapore due to local resistance patterns and regulatory nuances. Our pharmacy service bridges that gap, offering discreet, reliable delivery of both brand-name and generic formulations at competitive rates, while complying with international quality standards.
Brand Names and Generic Options
- Resochin - classic brand, 250 mg tablets.
- Nivaquine - 250 mg tablet, marketed in several Asian markets.
- Aralen - 250 mg tablet, often used for prophylaxis.
- Generic chloroquine phosphate - identical active ingredient, typically 20 % cheaper per tablet compared with branded versions.
Quality & Safety
We partner with licensed international pharmacies that operate under stringent regulatory frameworks recognized by the WHO and the Singapore HSA, ensuring each batch meets pharmaco-peia specifications.
Pricing & Access
Generic tablets are priced at approximately SGD .35 per 250 mg tablet, while branded options range from SGD .70 to SGD 1.20. Customers enjoy a lifetime 10 % discount on all reorders, making long-term therapy more affordable.
Discreet Delivery
Orders ship via express (≈ 7 days) or standard (≈ 3 weeks) services, enclosed in plain, tamper-evident packaging that protects privacy and product integrity.
Dosing, Formulations & Administration
Available Formulations
Chloroquine is supplied primarily as 250 mg immediate-release tablets. Some markets also offer syrup formulations for pediatric use, but these are rarely used in adult Singaporean practice.
Typical Dosing Ranges
- Acute malaria treatment: 600 mg (base) orally at time , followed by 300 mg at 24 h and 48 h.
- Chemoprophylaxis: 300 mg tablet taken once weekly, starting 1 week before exposure and continuing for 4 weeks after leaving the endemic area.
- Autoimmune indications (off-label): 250 mg daily, often titrated based on clinical response and tolerability.
These examples reflect common clinical practice; the exact dose must be individualized by a qualified healthcare professional.
Administration Guidelines
Chloroquine tablets may be taken with food to reduce gastrointestinal upset, although absorption is not significantly altered. Patients should avoid concomitant use of medications that prolong the QT interval and should refrain from excessive alcohol, which can increase hepatic metabolism variability.
Never adjust the dose without guidance from a clinician; a prescriber will decide the optimal regimen based on disease severity, comorbidities, and laboratory monitoring.
Safety Profile & Considerations
Common Side Effects
- Nausea and vomiting - reported in >10 % of acute treatment courses.
- Headache - occurs in 8-12 % of patients.
- Pruritus (skin itching) - especially in individuals of African descent, seen in up to 15 % of users.
- Retinal pigment changes - subtle visual disturbances may appear after prolonged use (>6 months).
Serious Adverse Events
- Retinopathy - irreversible macular damage can develop with cumulative doses >1 g/kg; regular ophthalmologic screening is essential.
- Cardiac toxicity - QT-interval prolongation and rare arrhythmias, particularly when combined with other QT-prolonging drugs.
- Severe hypoglycemia - especially in diabetic patients on insulin or sulfonylureas.
Contraindications
- Known hypersensitivity to chloroquine or related 4-aminoquinolines.
- Pre-existing retinal disease or compromised visual acuity.
- G6PD deficiency (risk of hemolysis).
- Current use of class Ia antiarrhythmics (e.g., quinidine) or drugs that markedly prolong QT interval.
Drug Interactions
- CYP2D6 inhibitors (e.g., fluoxetine, paroxetine) may increase chloroquine plasma levels.
- Other QT-prolonging agents (e.g., azithromycin, haloperidol) heighten arrhythmia risk.
- Antacids - may reduce absorption if taken within 2 hours of the dose.
Patients should provide a complete medication list to their prescriber before initiating therapy.
Special Populations
- Pregnancy: Chloroquine crosses the placenta; limited data suggest relative safety in the first trimester, but potential fetal retinal effects warrant caution in later stages.
- Breastfeeding: Small amounts are excreted in milk; monitoring of infant’s cardiac and visual development is advised.
- Older adults: Reduced renal clearance may necessitate dose adjustment; heightened vigilance for cardiac side effects.
- Hepatic or renal impairment: Accumulation risk increases; dose reductions or extended dosing intervals are often required under clinical supervision.
Frequently Asked Questions
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How does chloroquine differ from hydroxychloroquine? Both belong to the 4-aminoquinoline class, but hydroxychloroquine contains an additional hydroxyl group, resulting in a slightly better safety profile-particularly lower retinal toxicity-while retaining comparable antimalarial activity.
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How long before chloroquine produces noticeable effects for malaria? Parasite clearance usually begins within 24 hours of the first dose, with fever resolution typically observed by the second day of therapy.
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What should I do if I develop mild nausea after taking chloroquine? Taking the tablet with a small meal or snack often reduces gastrointestinal upset. Persistent nausea warrants a call to your healthcare provider for possible anti-emetic support.
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Can chloroquine be taken with food, and does it affect absorption? Food does not significantly alter bioavailability, but a light meal can improve tolerability and lessen stomach irritation.
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What are the signs of chloroquine-induced retinal toxicity? Early symptoms include blurred vision, difficulty reading, and altered color perception. Prompt ophthalmologic evaluation is essential if any visual change occurs.
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Is chloroquine safe for people with heart rhythm problems? Individuals with a history of QT prolongation or who use other QT-prolonging drugs should avoid chloroquine unless a cardiologist explicitly approves its use and monitors cardiac rhythm.
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Does chloroquine interact with common over-the-counter supplements? Herbal products containing quinidine-like alkaloids (e.g., certain traditional antimalarial teas) may amplify cardiac effects. Always disclose supplement use to your prescriber.
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What information should I provide my doctor when discussing chloroquine?
- Full list of prescription and over-the-counter medications, including supplements.
- History of cardiac disease, arrhythmias, or prolonged QT interval.
- Any known eye conditions or visual disturbances.
- Presence of G6PD deficiency or other metabolic disorders.
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Can chloroquine be used for malaria prophylaxis in Singapore travelers? Yes, for destinations where chloroquine-sensitive strains predominate. The regimen involves a 300 mg weekly dose, initiated one week before travel and continued for four weeks after return.
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Is there a risk of hypoglycemia for non-diabetic patients on chloroquine? While rare, chloroquine can lower blood glucose levels; monitoring is advisable for anyone with fluctuating sugar control.
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How often should I have eye examinations while on long-term chloroquine therapy? Baseline retinal imaging before starting treatment, followed by annual examinations after six months of continuous use, is the standard recommendation.
Disclaimer
The information provided about chloroquine is for general knowledge only. It does not replace professional medical consultation or the official prescribing information for medications containing this ingredient. All treatment decisions, including dosing, formulation selection, and monitoring, should be made under the supervision of a qualified healthcare provider who can assess individual medical history, current medications, and specific health needs. We assume all readers are responsible adults capable of making informed decisions about their health. Our online pharmacy offers access to medications containing chloroquine for individuals who may have limited availability through traditional pharmacies, prescription-based insurance schemes, or who are seeking affordable generic alternatives. Always consult your doctor before starting, changing, or discontinuing any medication containing chloroquine.