Treatment with Clozapine

You must have a heart cardiogram (ECG) before starting treatment, while the dose is being increased, and every six months during your treatment. An ECG measures the electrical activity of your heart.

You must have blood tests done before starting treatment and then every week for the first 18 weeks.

It is one of the most effective medicinal products against delusions and hallucinations in connection with schizophrenia.

Clozapine is used when other medicinal products do not provide an adequate effect or cause unacceptable side effects.

However, Clozapine also requires extra monitoring because it may cause severe side effects in a small number of people.

Side effects may include:

• Increased saliva production – especially at night. You can get medication that reduces the discomfort.
• Weight gain
• Constipation, which may be severe and require treatment
• Tiredness
• Dizziness
• Heart palpitations
• In rare cases, Clozapine may weaken your immune system (causing low white blood cell count). This can lead to serious infections.
• Inflammation of the heart may occur in a very small number of patients. The symptoms may resemble an acute heart attack. Therefore, you will have an electrocardiogram (ECG) done regularly.

Remember to inform your therapist if you experience any of the above side effects. You must also mention if you experience any other side effects that may be caused by your treatment with Clozapine.

If you forget to take a dose, take it as soon as you remember it, unless it is soon time for the next dose. In that case, simply follow your usual dosage schedule.

Do not take a double dose to make up for a missed dose.

NOTE: If more than 48 hours have passed, you will need a new dose escalation plan. Consult your therapist before taking the medication.

Always consult your therapist if you want to stop taking the medication or reduce the dose!

It is important to inform the doctor about any medication you are taking. Also tell your therapist if you start – or stop – taking other medication while you are being treated with Clozapine.

Smoking affects the amount of medication you need. If you smoke tobacco, the medication is less effective.  It is therefore important that you tell your therapist if you:

• start smoking tobacco
• quit smoking tobacco
• change your consumption (for example if you start smoking fewer or more cigarettes than usual)
• use other nicotine products, such as e-cigarettes or nicotine pouches.

Caffeine affects the concentration of Clozapine in the blood. It is therefore important that you tell your therapist if you change your consumption of caffeinated beverages such as coffee, tea or energy drinks.

Please note that Clozapine may make you feel more hungry, which can lead to weight gain.

Please note that alcohol increases the sedative effect of Clozapine.

Both cannabis and other intoxicants can cause severe and enhanced side effects.

As long as you are being treated with Clozapine, you must come for a check-up at the clinic at least every six months. Your doctor will check that you do not suffer severe side effects from the medication.

As there have been rare cases of severe side effects from Clozapine, it is very important that you come for the check-ups.

• You must have blood tests done every month.
• You must have an electrocardiogram (ECG) done at least every six months.
• You will also be weighed, as some people experience weight gain when treated with Clozapine.

You can consult your doctor if you want to know more about treatment with Clozapine.

You can read more about Clozapine in the leaflet Medication for psychosis. You can also find more information at: www.min.medicin.dk