Costco Pharmacy - Medications - Plaquenil - hydroxychloroquine
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication.
If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- diarrhea
- dizziness
- hair loss
- headache
- increased skin sensitivity to sunlight
- loss of appetite
- nausea
- skin rash
- stomach cramps or pain
- vomiting
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- blurred vision or any change in vision – this effect may also occur or worsen after stopping the medication
- change in colour of hair or skin pigment
- flu-like symptoms (sudden lack of energy, fever, cough, sore throat)
- hallucinations (seeing or hearing things that are not there)
- mood or other mental changes
- muscle weakness
- ringing or buzzing in ears or any loss of hearing
- signs of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
- signs of bleeding (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
- signs of heart problems (e.g., fast, irregular heartbeat or pulse, chest pain, sudden weight gain, difficulty breathing, leg swelling)
- signs of infection (symptoms may include fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
- signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
- signs of low blood sugar (hypoglycemia) (e.g., blurred vision, dizziness, fatigue, headache, numbness or tingling of the mouth, rapid heartbeat, shakiness, sweating or confusion)
- tingling, numbness or burning pain
- unusual tiredness or weakness
Stop taking the medication and seek immediate medical attention if any of the following occur:
- convulsions (seizures)
- extrapyramidal symptoms (abnormal body movements, restlessness, shaking, or stiffness)
- signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort
- signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
- thoughts of suicide or self-harm
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Blood tests: If you take this medication for a long period of time, your doctor will likely want you to have blood tests to monitor your levels of red and white blood cells.
Blood sugar levels: Hydroxychloroquine may cause hypoglycemia (low blood sugar levels). People with diabetes may find it necessary to monitor their blood sugar more frequently while using this medication. People without diabetes have also been known to experience low blood sugars while taking hydroxychloroquine. If you experience signs of low blood sugar (cold sweat, cool pale skin, headache, or weakness), contact your doctor immediately.
Blurred vision: While taking this medication, use caution when driving or operating machinery, since hydroxychloroquine can cause blurring of vision. If your vision blurs, call your doctor.
Eye damage: Irreversible damage to the retina of the eye has occurred for some people who take long-term or high-dosage treatment with hydroxychloroquine. Eye damage is more likely to occur if recommended doses are exceeded. Your doctor will want you to have regular eye exams if you take this medication for a period of time. If you notice any new problems with sight or symptoms such as light flashes and streaks, stop the medication at once and call your doctor.
Heart disease: Rarely, weakening of the heart muscle has been reported with the use of hydroxychloroquine. If you have heart disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Kidney disease: If you have kidney disease, you may need a lower dose of this medication. Talk to your doctor about how this medication may affect your medical condition, how the medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Liver disease: If you have liver disease, you may need a lower dose of this medication. Talk to your doctor about how this medication may affect your medical condition, how the medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Muscle weakness: Call your doctor if you notice any signs of unusual or unexpected muscular weakness.
Other medical conditions: If you have stomach, nerve, blood, or skin disorders, talk to your doctor about how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Suicidal behaviour: Rarely, people taking this medication may feel agitated (restless, anxious, aggressive, emotional, and feeling not like themselves), or they may want to hurt themselves or others. These symptoms may occur within several weeks after starting this medication. If you experience these side effects or notice them in a family member who is taking this medication, contact your doctor immediately. You should be closely monitored by your doctor for emotional and behaviour changes while taking this medication.
Pregnancy: Hydroxychloroquine crosses the placenta during pregnancy and may cause harm to the developing baby if it is taken by the mother during pregnancy. This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: This medication passes in small amounts into breast milk. Infants are extremely sensitive to its side effects. If you are a breast-feeding mother and are taking hydroxychloroquine, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using this medication have not been established for children when used for the treatment of rheumatoid arthritis or systemic lupus erythematosus. Children are especially sensitive to the side effects of hydroxychloroquine.
What other drugs could interact with this medication?
There may be an interaction between hydroxychloroquine and any of the following:
- albendazole
- amiodarone
- beta-adrenergic blockers (e.g., atenolol, propranolol, sotalol)
- chlorpromazine
- cyclosporine
- dapsone
- diabetes medications (e.g., glyburide, chlorpropamide, insulin, rosiglitazone)
- digoxin
- leflunomide
- live vaccines (e.g., BCG, yellow fever, measles, mumps, rubella)
- mebendazole
- mefloquine
- methotrimeprazine
- perphenazine
- praziquantel
- prochlorperazine
- pyrantel pamoate
- thioridazine
- trifluoperazine
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.