In this drug factsheet:
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.
- agitation (more common for seniors)
- bitter taste in mouth
- decreased muscle tone
- difficulty speaking
- dry mouth
- fast, irregular, or pounding heartbeat (more common for seniors)
- feeling of heaviness of arms and legs
- impaired vision
- increase in the amount of saliva (more common for seniors)
- increased appetite
- increased sweating (more common for seniors)
- loss of appetite (more common for seniors)
- stomach upset
- tingling, burning, or prickly sensation
- trembling and shaking of fingers, hands, arms, feet, or legs (more common for seniors)
- vomiting (more common for seniors)
- weight loss
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- behaviour changes
- clumsiness or unsteadiness (more common for seniors)
- confusion (more common for seniors)
- daytime anxiety or restlessness
- difficult or laboured breathing
- difficulty with coordination (more common for seniors)
- drowsiness (severe)
- memory problems (more common for seniors)
- mood or mental changes
- shortness of breath
- skin rash
- tightness in chest
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.
Anxiety or restlessness: An increase in daytime anxiety or restlessness has been observed during treatment with zopiclone.
Bad taste in mouth: Zopiclone may cause you to have a coated tongue, bad breath, or a bitter taste in your mouth. These effects often occur when this medication is being used.
Behaviour changes: This medication may worsen symptoms of depression, including thoughts of suicide or wanting to harm others. It may also cause agitated or aggressive behaviour. If you experience these symptoms or any other behaviour change while taking this medication, contact your doctor immediately.
Family members or caregivers of people who are taking this medication should contact the person's doctor immediately if they notice unusual behaviour changes.
Confusion: This medication affects mental efficiency (e.g., concentration, attention, and vigilance). The risk of confusion is greater for seniors and those with brain damage.
Drowsiness/reduced alertness: Zopiclone can cause excessive drowsiness and decreased mental alertness. Do not operate heavy machinery or drive after taking this medication.
Medical conditions: If you have depression, breathing problems, or liver impairment, 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.
Memory disturbance: Amnesia of varying severity has been reported following normal doses of medications like zopiclone. This effect is rare with zopiclone.
Performing activities while not fully awake: People taking zopiclone may perform activities such as sleepwalking, driving, preparing and eating food, and making phone calls while not fully awake and unaware of their actions. The next morning, they may not remember what happened. This may be more likely to occur if you use alcohol or other sedative medications. If you discover this has happened to you, contact your doctor immediately.
Withdrawal: Zopiclone can become habit-forming. Withdrawal symptoms similar to those occurring with related substances, including alcohol, have been observed after stopping the medication suddenly (after having taken it regularly over a period of time). These symptoms include:
- abdominal cramps
- extreme anxiety
- memory impairment
- muscle pain
- sleep problems such as rebound insomnia
Pregnancy: The safety of using this medication during pregnancy has not been established. This medication should not be used during pregnancy unless the benefits outweight the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking zopiclone, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of zopiclone have not been established for use by children and adolescents under 18 years of age.
Seniors: People over 65 years of age are more likely to experience dose-related side effects of zopiclone, such as drowsiness, dizziness, or impaired coordination. Using doses that are too high may result in accidents such as falls. Talk to your doctor if you are a senior and are experiencing any of the above side effects.
What other drugs could interact with this medication?
There may be an interaction between zopiclone and any of the following:
- anti-anxiety medications (e.g., clonazepam, lorazepam)
- anticonvulsants (medications used to prevent seizures; e.g., phenytoin, valproic acid, carbamazepine)
- antihistamines that cause drowsiness (e.g., diphenhydramine)
- antipsychotic medications or mood altering medications
- antipsychotics (e.g., olanzapine, quetiapine)
- ketoconazole, itraconazole, voriconazole
- narcotic or opioid medications (e.g., morphine, codeine)
- rifampicin or rifampin
- sedatives or tranquilizers (e.g., diazepam)
- St. John's wort
- tricyclic antidepressants
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.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.