How does Zyquenil work?
Hydroxychloroquinine is used in the treatment of some auto-immune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. In these diseases the body’s immune system is over-active and slightly defective. The body develops antibodies which attack and cause damage to its own cells. Damage can occur anywhere in the body, such as in the joints or cartilage as in the case of rheumatoid arthritis. As a result of the damage to the joints, reduced mobility and stiffness in the affected joints is experienced.
Hydroxychloroquine is thought to act by interfering with the production and release of blood cells that are involved in the body’s immune defence system. Hence the autoimmune response of the antibodies against its own body, is reduced and as result the amount of damage to the cells is minimized and prevented. As it has the potential to prevent progression of the disease, by limiting the damage caused, it is often referred to as a disease-modifying antirheumatic drug (DMARDS) and is commonly used very early in the treatment of rheumatoid arthritis.
Hydroxychloroquine is also used in treating skin conditions that are caused or aggravated by sunlight.
What is Zyquenil used for?
• Inflammatory disease of the joints (rheumatoid arthritis)
• Long-term inflammation of skin and some internal organs (systemic lupus erythematosus) or related diseases e.g. scleroderma
• Severe inflammatory diease of the joint that commonly occurs in children and adolescents (juvenile arthritis)
• Skin damaged by the sun
• Skin disorders caused or made worse by sunlight
• This medication may cause a blurring of vision. If affected do not drive or operate machinery.
• People taking this medicine should have regular blood tests to check the levels of their blood components.
• It is recommended that eye examinations are carried out before starting treatment with this medicine and repeated every six months in the course of the treatment. This medicine should be discontinued if any visual problems develop.
Use with caution in
• Conditions involving the stomach and intestines (gastrointestinal conditions)
• Disease affecting the brain and nervous system (neurological disease)
• Individuals taking medicines that may cause skin reactions or impair vision
• Kidney disease
• Lack of the enzyme G6PD in the blood (G6PD deficiency)
• Life long inherited blood diseases which can cause a variety of symptoms, including mental health problems (porphyrias)
• Liver disease
• Severe blood disorders
Not to be used in
• Allergy to quinine
• Pre-existing abnormality of the eye (eye maculopathy)
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and Breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
• This medicine should not be used in pregnancy. Seek medical advice from your doctor.
• This medicine passes into breast milk in small amounts. Seek medical advice from your doctor before breastfeeding.
• Do not take indigestion remedies at the same time of day as this medication.
• Take this medication with or after food.
Hydroxychloroquine side effects
Applies to Hydroxychloroquine: oral tablet
As well as its needed effects, Hydroxychloroquine (the active ingredient contained in Hydroxychloroquine) may cause unwanted side effects that require medical attention. When this medicine is used for short periods of time, side effects usually are rare. However, when it is used for a long time and/or in high doses, side effects are more likely to occur and may be serious.
Major Side Effects
You should not use this medication if you are allergic to Hydroxychloroquine, or if you have a history of vision changes or damage to your retina caused by Hydroxychloroquine or similar anti-malaria medications.
Before using Hydroxychloroquine, tell your doctor if you are allergic to any drugs, or if you have psoriasis, porphyria, liver disease, alcoholism, or glucose-6-phosphate dehydrogenase (G-6-PD) deficiency.
Call a poison control center at once and then seek emergency medical attention if you think you have used too much of this medicine. An overdose of Hydroxychloroquine can be fatal, especially in children.
Take this medicine for the full prescribed length of time for malaria. Your symptoms may improve before the infection is completely cleared.
Contact your doctor as soon as possible if you have been exposed to malaria, or if you have fever or other symptoms of illness during or after a stay in an area where malaria is common.
When treating lupus or arthritis, tell your doctor if your symptoms do not improve after 6 months of treatment.
While using Hydroxychloroquine, you may need frequent blood tests at your doctor’s office.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
• Blurred vision
• Changes in skin pigmentation
• Dislike of light (photophobia)
• Balance problems involving the inner ear (vertigo)
• Hair loss (alopecia)
• Disorders of the front layer of the eye (cornea)
• Worsening of the skin condition psoriasis
• Gastric disturbances including nausea, vomiting, gastric discomfort, constipation, diarrhea
• Worsening of porphyria
• Disorder of the retina resulting in impairment or loss of vision.
The side effects listed above may not include all of the side effects reported by the drug’s manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
Hydroxychloroquine may increase the blood levels of digoxin, resulting in an increased risk of side-effects or toxicity. Therefore close monitoring is required.
The absorption of hydroxychloroquine may be reduced by antacids (indigestion remedies). It is advisable to leave a 4-hour interval between the two doses.
What is Hydroxychloroquine?
Hydroxychloroquine belongs to the family of medicines called antiprotozoals. Protozoa are tiny, one-celled animals. Some are parasites that can cause many different kinds of infections in the body.
Hydroxychloroquine is used to prevent and to treat malaria and to treat some conditions such as liver disease caused by protozoa. It is also used in the treatment of arthritis to help relieve inflammation, swelling, stiffness, and joint pain and to help control the symptoms of lupus erythematosus (lupus; SLE).
Hydroxychloroquine may be given alone or with one or more other medicines. It may also be used for other conditions as determined by your doctor.
Hydroxychloroquine is available only with your doctor’s prescription.
Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, Hydroxychloroquine is used in certain patients with the following medical conditions:
- Arthritis, juvenile
- Vasculitis, chronic cutaneous
Rheumatoid arthritis; Systemic lupus erythematosus
Adult: Initially, 400 mg daily in divided doses.
Maintenance: 200-400 mg/day. Max: 6.5 mg/kg/day or 400 mg/day whichever is lower.
Child: Up to 6.5 mg/kg/day or 400 mg/day whichever is lower. Lowest effective dose should be used.
Renal impairment: Estimation of plasma Hydroxychloroquine levels to be undertaken in patients with severely compromised function and dosage adjusted accordingly.
Hepatic impairment: Estimation of plasma Hydroxychloroquine levels to be undertaken in patients with severely compromised function and dosage adjusted accordingly.
Prophylaxis of malaria
Adult: 400 mg every 7 days. Begin 2 wk before exposure, continue for 4-6 wk after leaving the endemic area.
Child: 6.5 mg/kg once wkly. Max: 400 mg/dose.
Adult: Initially, 800 mg followed by 400 mg 6-8 hr later, then a further 400 mg on each of the succeeding 2 days.
Child: 13 mg/kg; followed by 6.5 mg/kg 6 hr later and repeat dose on the 2nd and 3rd days.
How should I use Hydroxychloroquine?
Use Hydroxychloroquine as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take Hydroxychloroquine by mouth with food or a full glass of milk (8 oz/240 mL).
- If possible, preventative measures for malaria should begin 2 weeks before exposure and be continued for 8 weeks after leaving the endemic area.
- If you are taking Hydroxychloroquine for lupus or arthritis, it may take 4 to 12 weeks for Hydroxychloroquine to work.
- If you miss a dose of Hydroxychloroquine, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use Hydroxychloroquine.
Uses of Hydroxychloroquine in details
Use: Labeled Indications
Lupus erythematosus: Treatment of chronic discoid erythematosus and systemic lupus erythematosus in adults.
Malaria: Treatment of uncomplicated malaria caused by susceptible strains of Plasmodium vivax, Plasmodium malariae, Plasmodium ovale, and Plasmodium falciparum; prophylaxis of malaria in geographic areas where chloroquine resistance is not reported.
Limitations of use: Hydroxychloroquine is not effective against chloroquine- or Hydroxychloroquine-resistant malaria strains of Plasmodium species; not recommended for treatment of complicated malaria, malaria prophylaxis in regions with chloroquine resistance, or treatment when the Plasmodium species has not been identified; Hydroxychloroquine does not prevent relapses of P. vivax and P. ovale infections because it is not effective against the hypnozoite forms of these parasites.
Rheumatoid arthritis: Treatment of acute and chronic rheumatoid arthritis in adults.
Off Label Uses
Coronavirus disease 2019 (COVID-19)
Data from a limited number of hospitalized patients in a small number of studies suggest varying clinical results for the use of Hydroxychloroquine in the treatment of coronavirus disease 2019 (COVID-19).
The prototypical antimalarial agent with a mechanism that is not well understood. It has also been used to treat rheumatoid arthritis, systemic lupus erythematosus, and in the systemic therapy of amebic liver abscesses.
One Hydroxychloroquine tablet contains 200 mg of Hydroxychloroquine, which is equivalent to 155 mg base.
Take Hydroxychloroquine with a meal or a glass of milk.
Adults: 400 mg (310 mg base) once weekly on the same day of each week starting 2 weeks prior to exposure, and continued for 4 weeks after leaving the endemic area.
Weight-based dosing in adults and pediatric patients: 6.5 mg/kg (5 mg/kg base), not to exceed 400 mg (310 mg base), once weekly on the same day of the week starting 2 weeks prior to exposure, and continued for 4 weeks after leaving the endemic area.
Treatment of Uncomplicated Malaria
Adults: 800 mg (620 mg base) followed by 400 mg (310 mg base) at 6 hours, 24 hours and 48 hours after the initial dose (total 2000 mg Hydroxychloroquine or 1550 mg base).
Weight based dosage in adults and pediatric patients: 13 mg/kg (10 mg/kg base), not to exceed 800 mg (620 mg base) followed by 6.5 mg/kg (5 mg/kg base), not to exceed 400 mg (310 mg base), at 6 hours, 24 hours and 48 hours after the initial dose. Hydroxychloroquine film-coated tablets cannot be divided, therefore they should not be used to treat patients who weigh less than 31 kg.
For radical cure of P. vivax and P. malariae infections, concomitant therapy with an 8-aminoquinoline compound is necessary.
The recommended adult dosage is 200 to 400 mg (155 to 310 mg base) daily, administered as a single daily dose or in two divided doses. Doses above 400 mg a day are not recommended.
The incidence of retinopathy has been reported to be higher when this maintenance dose is exceeded.
The action of Hydroxychloroquine is cumulative and may require weeks to months to achieve the maximum therapeutic effect.
Dosage: 400 mg to 600 mg (310 to 465 mg base) daily, administered as a single daily dose or in two divided doses. In a small percentage of patients, side effects may require temporary reduction of the initial dosage.
Dosage: When a good response is obtained, the dosage may be reduced by 50 percent and continued at a maintenance level of 200 mg to 400 mg (155 to 310 mg base) daily, administered as a single daily dose or in two divided doses.
Do not exceed 600 mg or 6.5 mg/kg (5 mg/kg base) per day, whichever is lower, as the incidence of retinopathy has been reported to be higher when this maintenance dose is exceeded.
Corticosteroids and salicylates may be used in conjunction with Hydroxychloroquine, and they can generally be decreased gradually in dosage or eliminated after a maintenance dose of Hydroxychloroquine has been achieved.
Androgens: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Exceptions: Danazol. Monitor therapy
Antidiabetic Agents: May enhance the hypoglycemic effect of Hypoglycemia-Associated Agents. Monitor therapy
Antipsychotic Agents (Phenothiazines): Antimalarial Agents may increase the serum concentration of Antipsychotic Agents (Phenothiazines). Monitor therapy
Artemether: May enhance the adverse/toxic effect of Antimalarial Agents. Management: Artemether/Lumefantrine (combination product) should not be used with other antimalarials unless there is no other treatment option. Avoid combination
Beta-Blockers: Aminoquinolines (Antimalarial) may decrease the metabolism of Beta-Blockers. Exceptions: Atenolol; Carteolol (Ophthalmic); Levobunolol; Metipranolol; Nadolol; Sotalol. Monitor therapy
Cardiac Glycosides: Aminoquinolines (Antimalarial) may increase the serum concentration of Cardiac Glycosides. Monitor therapy
Citalopram: May enhance the hypoglycemic effect of Hydroxychloroquine. Hydroxychloroquine may enhance the QTc-prolonging effect of Citalopram. Monitor therapy
Dapsone (Systemic): Antimalarial Agents may enhance the adverse/toxic effect of Dapsone (Systemic). Specifically, concomitant use of antimalarial agents with dapsone may increase the risk of hemolytic reactions. Dapsone (Systemic) may enhance the adverse/toxic effect of Antimalarial Agents. Specifically, concomitant use of dapsone with antimalarial agents may increase the risk for hemolytic reactions. Management: Closely monitor patients for signs/symptoms of hemolytic reactions with concomitant use of dapsone and antimalarial agents, particularly in patients deficient in glucose-6-phosphate dehydrogenase (G6PD), methemoglobin reductase, or with hemoglobin M. Consider therapy modification
Dapsone (Topical): Antimalarial Agents may enhance the adverse/toxic effect of Dapsone (Topical). Specifically, the risk of hemolytic reactions may be increased. Management: Closely monitor for signs/symptoms of hemolytic reactions with concomitant use of topical dapsone and antimalarial agents. Patients with glucose-6-phosphate dehydrogenase deficiency may be at particularly high risk for adverse hematologic effects. Consider therapy modification
Escitalopram: May enhance the hypoglycemic effect of Hydroxychloroquine. Hydroxychloroquine may enhance the QTc-prolonging effect of Escitalopram. Monitor therapy
Haloperidol: QT-prolonging Agents (Indeterminate Risk – Avoid) may enhance the QTc-prolonging effect of Haloperidol. Monitor therapy
Herbs (Hypoglycemic Properties): May enhance the hypoglycemic effect of Hypoglycemia-Associated Agents. Monitor therapy
Hypoglycemia-Associated Agents: May enhance the hypoglycemic effect of other Hypoglycemia-Associated Agents. Monitor therapy
Lumefantrine: Antimalarial Agents may enhance the adverse/toxic effect of Lumefantrine. Management: Artemether/Lumefantrine (combination product) should not be used with other antimalarials unless there is no other treatment option. Avoid combination
Maitake: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Monitor therapy
Mefloquine: Aminoquinolines (Antimalarial) may enhance the adverse/toxic effect of Mefloquine. Specifically, the risk for QTc-prolongation and the risk for convulsions may be increased. Mefloquine may increase the serum concentration of Aminoquinolines (Antimalarial). Management: Avoid concurrent use, and delay administration of mefloquine until at least 12 hours after the last dose of an aminoquinoline antimalarial when possible. Avoid combination
Monoamine Oxidase Inhibitors: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Monitor therapy
Pegvisomant: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Monitor therapy
Prothionamide: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Monitor therapy
QT-prolonging Agents (Highest Risk): QT-prolonging Agents (Indeterminate Risk – Avoid) may enhance the QTc-prolonging effect of QT-prolonging Agents (Highest Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Monitor therapy
Quinolones: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Quinolones may diminish the therapeutic effect of Agents with Blood Glucose Lowering Effects. Specifically, if an agent is being used to treat diabetes, loss of blood sugar control may occur with quinolone use. Monitor therapy
Salicylates: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Monitor therapy
Selective Serotonin Reuptake Inhibitors: May enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Monitor therapy
Tamoxifen: May enhance the adverse/toxic effect of Hydroxychloroquine. Specifically, concomitant use of tamoxifen and Hydroxychloroquine may increase the risk of retinal toxicity. Monitor therapy
Active ingredient matches for Hydroxychloroquine:
List of Hydroxychloroquine substitutes (brand and generic names):
HYDROWIN (India) HYDROWIN tab 400 mg x 10’s (Ikon)$ 1.69 HYDROXYCHLOROQUINE 200MG TABLET HYDROXYCHLOROQUINE 200MG TABLET 1 strip / 10 tablets each (Jan Aushadhi)$ 0.60 Hydroxychloroquine AN (Australia) Hydroxychloroquine GH (Australia) Hydroxychloroquine RBX (Australia) Hydroxychloroquine Sulfate 100 tablet in 1 bottle 500 tablet in 1 bottle Hydroxychloroquine Sulfate tablet 200 mg/1 (Avera Mc Kennan Hospital (US)) Hydroxychloroquine Sulfate tablet, film coated 200 mg/1 (Zydus Pharmaceuticals (USA, US) Inc.) Hydroxychloroquine Sulfate tablet, coated 200 mg/1 (Watson Laboratories, Inc. (US)) Hydroxychloroquine Sulfate Actavis (United States) Hydroxychloroquine Sulfate Lenis (Slovenia) Hydroxychloroquine Sulphate P & D (Malta) Hydroxychloroquine Tablets Hydroxychloroquine Zentiva (Switzerland) Hydroxychloroquine Zentiva 200mg (Switzerland) Hydroxychloroquinesulfaat (Netherlands) Hydroxychloroquinesulfaat CF (Netherlands) HYQ HYQ 400 MG TABLET 1 strip / 10 tablets each (Ipca Laboratories Ltd)$ 1.86 Hyq 400mg Tablet (Ipca Laboratories Ltd)$ 0.19 Ilinol (Chile) Immard Tablet, Film-Coated; Oral; Hydroxychloroquine Sulfate 200 mg Lisen (Taiwan) Lisen 200 mg x 1000’s Mcqs (India) Mcqs 200mg TAB / 10 (Molekule)$ 1.11 200 mg x 10’s (Molekule)$ 1.11 MCQS 200MG TABLET 1 strip / 10 tablets each (Molekule)$ 1.11 MCQS tab 200 mg x 10’s (Molekule)$ 1.11 Mcqs 200mg Tablet (Molekule)$ 0.11 Metirel (Argentina) Mylan-Hydroxychloroquine (Canada) Tablet; Oral; Hydroxychloroquine Sulfate 200 mg Mylan-hydroxychloroquine tablet 200 mg (Mylan Pharmaceuticals Ulc (Canada)) Narbon (Argentina) ORTHOKIND ORTHOKIND 200MG TABLET 1 strip / 10 tablets each (Mankind Pharma Ltd)$ 1.11 OXCQ (India) 10’s (Wallace Pharmaceuticals Ltd.)$ 0.95 OXCQ 400 mg Tablet (Wallace Pharmaceuticals Ltd.)$ 0.18 OXCQ 200 mg Tablet (Wallace Pharmaceuticals Ltd.)$ 0.10 Oxcq Hydroxychloroquine TAB / 10 (Wallace Pharmaceuticals Ltd.)$ 0.95 OXCQ 200 MG TABLET 1 strip / 10 tablets each (Wallace Pharmaceuticals Ltd.)$ 0.92 OXCQ 400 MG TABLET 1 strip / 10 tablets each (Wallace Pharmaceuticals Ltd.)$ 1.85 OXCQ tab 200 mg x 10’s (Wallace Pharmaceuticals Ltd.)$ 1.07 OXCQ tab 400 mg x 10’s (Wallace Pharmaceuticals Ltd.)$ 1.87 Oxcq Hydroxychloroquine TAB / 10 (Wallace Pharmaceuticals Ltd.)$ 0.95 See 186 substitutes for Hydroxychloroquine
- PubChem. “hydroxychloroquine”. https://pubchem.ncbi.nlm.nih.gov/com…
- DrugBank. “hydroxychloroquine”. http://www.drugbank.ca/drugs/DB01611
- MeSH. “Antirheumatic Agents”. https://www.ncbi.nlm.nih.gov/mesh/68…
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