These include:(very occasionally) breast growth and, in very rare instances, some milk flow, regardless of genderSome of these effects should pass after the first couple of weeks. It can also make your symptoms worse.Cannabis and other drugs may have their own side effects on your mental health, like anxiety or psychosis. For more information, have a look at our Methadone can make drowsiness worse with olanzapine and potentially cause dangerous problems with the rhythm of your heart.All antipsychotics can reduce the stimulant effects of cocaine.If you start or stop smoking while you are taking olanzapine, you may have to change your dose.Cigarette smoke affects the amount of olanzapine in your body.If you smoke, you may need a higher dose of olanzapine than someone who does not smoke.Tell your doctor if you smoke, so that you get the right dose for you.If you stop smoking, the level of olanzapine in the body rises, and you might need to reduce your dose of olanzapine slowly over one week.If you (re)start smoking, you may need to increase it againGo to your doctor for advice if you stop or start smoking.Olanzapine does not mix well with some other medicines and drugs. Discuss this with your doctor.Remember that it is important for you to stay well while you are bonding with and looking after your baby. A study of over 800 mums who took olanzapine during pregnancy suggested no increased risk of malformations, miscarriage or premature birth.Olanzapine may slightly increase your chance of getting high blood pressure linked to pregnancy (pre-eclampsia), putting on extra weight and gestational (pregnancy-linked) diabetes.Expect your blood sugar levels, weight and blood pressure to be more closely checked from month four onwards of your pregnancy if you are on olanzapine.Taking olanzapine close to delivery may lead to some discontinuation (withdrawal) effects in your baby. Both olanzapine and alcohol (beverage) can have CNS depressant effects, which might affect the ability to perform skilled tasks (see 'Drugs and Driving' in Guidance on Prescribing). This is the name that the manufacturer gives to the medicine, for example Zyprexa is a brand name for olanzapine.Olanzapine is an antipsychotic medicine, and is used to help treat people with schizophrenia and similar conditions such as psychosis. If they do not, and this is a problem for you, go back to the doctor and see what other medicines you could try.The good effects of olanzapine may have a positive impact on your sex life as your symptoms settle, and you can concentrate on your relationships.Olanzapine may increase the level of a hormone called prolactin in the body for a short time when you start taking it, but not to a very high level. Even so, specialists might prescribe it ‘Orodispersible tablets: 5mg, 10mg, 15mg and 20mg strengths (these may be called Zyprexa Velotabs®)N.B. Symptoms include:If you already have diabetes, you may need to increase the amount of medication you take for this alongside taking olanzapine. Tell your doctor before you take olanzapine if you are taking any other medicines.You should have your weight, blood sugar, blood fats, blood pressure and pulse measured regularly during early treatment, then at least every six months to a year after that, depending on your age.You should also have your blood sugar tested when you start, after one month, and then every four to six months after that.They might also check your height and development. If you are a parent needing help, please contact our helpline by phone, webchat or email.