Quiet

Indications

Quetiapine is used to treat schizophrenia and bipolar disorder (both episodes of mania and episodes of depression), and to help prevent new bipolar episodes. The extended-release form may also be added to an antidepressant for major depression when the antidepressant alone has not worked well enough.

How It Works

Quetiapine is an atypical antipsychotic. It balances the action of brain chemicals, mainly dopamine and serotonin, which helps reduce hallucinations, disturbed thinking, extreme mood swings and low mood.

Dosage and Administration

Take exactly as prescribed. Treatment starts at a low dose and is increased over several days. Usual adult doses range from about 150 to 750 mg a day depending on the condition, given as immediate-release tablets in two doses or as extended-release tablets once a day, often in the evening. Extended-release tablets must be swallowed whole, not crushed or chewed. Older people and people with liver problems usually need lower doses. Use in children and teenagers is only under a specialist.

Interactions

• Ketoconazole, Itraconazole, Clarithromycin, Erythromycin and Ritonavir can raise quetiapine levels a lot.
• Carbamazepine, Phenytoin and Rifampicin can lower its levels and make it less effective.
• Alcohol, sleeping pills, opioid painkillers and sedating antihistamines add to drowsiness.
• Medicines that affect heart rhythm (for example Amiodarone, some antibiotics and other antipsychotics) increase the risk of an irregular heartbeat.
• Grapefruit juice should be avoided.

Contraindications

Allergy to quetiapine or any ingredient of the product, and use together with strong enzyme blockers such as Ketoconazole, Itraconazole or Ritonavir.

Side Effects

Common: sleepiness, dizziness (especially when standing up), dry mouth, constipation, increased appetite and weight gain, raised blood sugar and cholesterol, and a fast heartbeat.

Get urgent medical help for: high fever with stiff muscles, sweating and confusion; fainting or a very fast or irregular heartbeat; a fit (seizure); uncontrollable movements of the face, tongue or body; signs of infection with fever and sore throat; severe rash or swelling of the face or throat; or worsening mood or thoughts of harming yourself.

Pregnancy and Lactation

Use in pregnancy only if the doctor decides the benefit outweighs the risk. Babies exposed in the last three months of pregnancy may have shakiness, stiffness, sleepiness or feeding problems after birth. Small amounts pass into breast milk; discuss with the doctor before breastfeeding. Do not stop the medicine on your own if you become pregnant.

Precautions and Warnings

• Older people with dementia have a higher risk of stroke and death with antipsychotics; quetiapine is not for dementia-related behaviour problems.
• Tell the doctor about heart disease, low blood pressure, diabetes, epilepsy, liver problems or high cholesterol. Weight, blood sugar and blood fats should be checked from time to time.
• Do not drive or operate machines until you know how it affects you. Avoid alcohol.
• Do not stop suddenly; the dose should be reduced slowly to avoid sleep problems, nausea and return of symptoms.

Overdose

Overdose can cause heavy drowsiness, very low blood pressure, a fast heartbeat, fits and coma. Take the person to an emergency department immediately and bring the medicine pack.

Therapeutic Class

Atypical (second-generation) antipsychotic.

Storage

Store below 30°C in a dry place, away from light and out of the reach of children.