Executive summary
This document provides a concise, practical summary of chloroquine as used in the Australian continent. It covers common uses, administration tips, dosing patterns, safety planning considerations, approximate retail housing costs in Australian dollars, and how this medicine is accessed locally. Skip ahead to the section on dosing and schedules or legally sanctioned access at any point.
- Active moiety: chloroquine. Products are frequently formulated as chloroquine phosphate; many dosing references show amounts as chloroquine base equivalents.
- Main use: antiprotozoal - principally antimalarial and for certain forms of amebiasis. Although investigated in other contexts, routine use remains antiparasitic.
- Common tablet sizes: 250 mg and 500 mg of chloroquine phosphate. A 500 mg phosphate tablet corresponds roughly to 300 mg chloroquine base.
- Brands: internationally known trade names include Aralen; in Australia generic supplies or travel-clinic stock may be the usual source.
Clues and rationale for use
Chloroquine is typically used for:
- Prevention (suppressive therapy) and treatment of malaria caused by Plasmodium vivax, P. malariae, P. ovale, and strains of P. falciparum that remain susceptible to chloroquine.
- Treatment of extraintestinal amebiasis. For a radical cure of P. vivax or Plasmodium. ovale infections, an additional 8-aminoquinoline such as primaquine is usually required when it is safe to do so.
Important message: chloroquine resistance in P. falciparum is widespread in many regions. Travel medicine recommendations frequently favour a substitute choice antimalarial drugs for travellers to affected areas.
Ways to take chloroquine
- Take each dose with food or milk if you get stomach discomfort, unless your prescriber gives other instructions.
- Comply precisely with the prescription. Do not increase dose or frequency without medical advice.
- For weekly prophylaxis regimens take the tablet on the same day each week to help remember it.
- Do not stop a prescribed course early even if symptoms improve; incomplete treatment can allow relapse or step back and return of infection.
- If you miss taking a dose, take it immediately after you remember, unless the timing for the next dose is near. Do not take two doses at once to replenish a i skipped the dose.
For dose specifics and schedules see Dosing intervals and schedules.
Dosing schedule and dosage information
Dosing is often expressed in terms of chloroquine base. As a guide only, a 500 mg chloroquine phosphate tablet provides about 300 mg chloroquine base. Pediatric doses should be weight-based. Always adhere to a clinician's prescription.
Malaria prevention by means of prophylaxis to suppress disease
- Adults: 500 mg chloroquine phosphate (approximately 300 mg base) taken once weekly on a chosen day.
- The infant population: usually 5 mg/kg of base per week, not exceeding the adult dose.
- Ideal start time is 1 to 2 weeks before entering an endemic area. If starting later, adults may use an initial loading dose of 1 g chloroquine phosphate (about 600 mg base) split into two doses 6 hours apart; children receive a corresponding weight-based loading regimen. Continue weekly while exposed and for 8 weeks after leaving the area.
Drugs used in acute malaria treatment options
- Adults: initial dose 1 g chloroquine phosphate (about 600 mg base), followed in 6 to 8 hours by 500 mg (about 300 mg base), then 500 mg once daily on the next two days. Total over 3 days approximately 2.5 g phosphate (about 1.5 g base
- Youngsters: dosing by weight (base): first dose 10 mg/kg (maximum single dose about 600 mg base), second dose 5 mg/kg after 6 hours (max about 300 mg), along with then 5 mg/kg at 24 and 36 hours after the initial dose.
- For a total cure of P. vivax or Plasmodium. ovale, add an appropriate 8-aminoquinoline regimen when indicated and safe.
Disseminated Entamoeba histolytica infection
- Adults: typical course begins with 1 g chloroquine phosphate (about 600 mg base) daily for two days, followed by 500 mg (about 300 mg base) daily for at least 2 to 3 weeks. This is usually combined with an effective luminal amebicide to clear intestinal carriage.
Storage unit
- Keep in a tightly closed container at normal room temperature, out of direct sunlight and away from heat and moisture.
- Do not store in the freezer.
- Keep medicines out of reach of kids and animals.
- Dispose of expired or unneeded tablets via a pharmacy take-back or local medication disposal program.
Advice on safety
- Eye surveillance of system activity: visual disturbances, blurred vision or reduced acuity can occur. Report any visual changes quickly; your doctor may arrange ophthalmology review for ongoing therapy.
- Long-term therapy: blood tests and clinical continuous oversight may be needed for prolonged use, including checks for muscle weakness or hematological changes.
- Be cautious with driving or operating machinery if vision or alertness is impaired.
- Tell your prescriber about regular alcohol, tobacco or other medication use to identify the networked exchange of ideass in a system describe exchanges between components..
- Pregnancy: treatment in pregnancy may be considered when the benefits outweigh risks; discuss with an obstetrician or infectious disease specialist as needed.
Possible effects to watch for
Most short courses are tolerated well but the chance of negative unintended effects increases with higher doses or longer treatment. Contact a healthcare professional for symptoms that are severe or persistent.
Seek rapid medical evaluation for severe abdominal pain
- Sudden vision loss, severe eye pain, or major changes in eyesight.
- Black or tarry stools, blood in urine or stools, unexplained bleeding or easy bruising, or pinpoint red spots on the skin.
- Epilepsy-related seizures, major mood changes, hearing loss or persistent ringing in the ears.
- High fever with sore throat or other signs of infection, fainting, or marked lightheadedness.
- New or worsening muscle weakness, painful or difficult urination, or flank pain.
Visual symptoms sometimes appear or progress after drug discontinuation. If this happens, seek evaluation promptly.
Symptoms and signs of an overdosed
- Drowsiness, severe aching head, restlessness or marked agitation. Excessive drug intake is a medical emergency and requires immediate care.
Effects that are typical or mild
- Nausea or sick to the stomach
- Itching (more frequent in some populations)
- Headache
- Acute diarrhoea
- Appetite wanes or stomach cramps
- Difficulty focusing or reading clearly
Reactions that are less commonly observed
- Hair discoloration or increased hair loss
- Blue-black pigmentation of skin, nails or inside the mouth
- Rash or other skin reactions
Any troublesome or unexpected effect should be discussed with your prescriber or pharmacist.
Alternative options and a price comparison study in AUD
Drug choice depends on travel destination, parasite species and resistance patterns, the patient's medical history and tolerability. The prices below are approximate retail ranges in Australia and will vary by brand, pack size, pharmacy, PBS listing and date of purchase.
Alternative measures for preventing or treating malaria
- Atovaquone/proguanil (e.g., 250 mg/100 mg): often recommended where chloroquine resistance exists. Typical price range AUD 60 to 120 for a pack covering a short trip.
- Doxycycline 100 mg: commonly used for prophylaxis in travellers. Approximate cost AUD 10 to 25 depending on count.
- Mefloquine 250 mg: weekly option for prophylaxis. Typical retail AUD 40 to 90 for a small pack.
- Artemisinin-based combination therapies (for treatment, not prophylaxis): artemether/lumefantrine is a common regimen, around AUD 40 to 100 per treatment course.
- Hydroxychloroquine 200 mg: related compound with different proof of; costs vary. On PBS the copayment is lower for listed proof of; private purchase may be AUD 60 to 100 for some packs.
- Chloroquine phosphate 500 mg: limited role due to resistance; if stocked, typical retail AUD 20 to 50 for small packs.
Amebiasis: a contingency option approaches
- Metronidazole: tissue-active drug for invasive disease, usually followed by a luminal agent. Approximate cost AUD 10 to 20 for a standard course.
- Tinidazole: similar to metronidazole in activity with some shorter regimens. Typical price AUD 8 to 15 for a single-dose or short-course supply.
- Paromomycin (luminal agent): availability can be limited and may require special supply channels; retail price can range from AUD 80 to 200 or more.
- Iodoquinol and diloxanide furoate: luminal agents with variable availability and widely differing costs if sourced specially.
Discuss options with a travel medicine clinic or infectious diseases specialist to choose the safest and most appropriate product for your situation.
Official status and access in Australia
- Prescription status: chloroquine is Schedule 4 (S4) in Australia and requires a prescription from an Australian-registered prescriber for supply from a pharmacy.
- Regulatory approval: products supplied in Australia must be registered with or supplied under pathways overseen by the Therapeutic Goods Administration (TGA).
- PBS and subsidies: some antimalarial medicines are listed on the Pharmaceutical Benefits Scheme for specific portents; patient copayments and availability depend on PBS status and clinical criteria.
- Personal importation: under the TGA Private Import Scheme individuals may import limited quantities of prescription medicines for personal use if they hold a valid prescription and meet scheme conditions. Be sure to check the logs TGA website for current limits and rules before importing.
- Prescriber restrictions: related medicines may have additional initiation or indication restrictions; always follow Australian clinical guidance and local policies.
- Travel advice: because of widespread resistance in many countries, travel health services often recommend other possibilities to chloroquine for many destinations. Obtain pre-travel consultation well before departure.
For clinical decisions and patient safety follow current Australian guidelines with the addition of the advice of registered health professionals. See Cost comparison and other possible paths for common substitute medicines.
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