Side Effects Of Olanzapine

Like all medicines, olanzapine can cause side effects, although not everyone gets them.

Common side effects of olanzapine

These common side effects of olanzapine may affect up to 1 in 10 people. There are things you can do to help cope with them:

Speak to a doctor or pharmacist if the advice on how to cope does not help and a side effect is still bothering you or does not go away.

See your doctor if you have sexual problems such as lower libido in men or women, or problems getting an erection. These can be signs of hormone changes.

Serious side effects

Serious side effects are rare and happen in less than 1 in 1,000 people.

Call your doctor or call 111 for advice now if:

• you get infections including coughs, colds and chest infections, ear and eye infections, or urinary tract infections (UTIs) - these can be signs of a low white blood cell count
• you get swelling, pain and redness in one leg - these can be signs of blood clots
• you get twitching or jerking movements in your face, tongue or other parts of your body
• you have difficulty walking or start shuffling slowly when you walk, trembling or shaking

Call 999 or go to A&E if:

Serious allergic reaction

In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to olanzapine.

Call 999 now if:

• your lips, mouth, throat or tongue suddenly become swollen
• you're breathing very fast or struggling to breathe (you may become very wheezy or feel like you're choking or gasping for air)
• your throat feels tight or you're struggling to swallow
• your skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)
• you suddenly become very confused, drowsy or dizzy
• someone faints and cannot be woken up
• a child is limp, floppy or not responding like they normally do (their head may fall to the side, backwards or forwards, or they may find it difficult to lift their head or focus on your face)

You or the person who's unwell may also have a rash that's swollen, raised, itchy, blistered or peeling.

These can be signs of a serious allergic reaction and may need immediate treatment in hospital.

Long-term side effects

Olanzapine can increase the amount of sugar in your blood and this can sometimes lead to diabetes. This affects less than 1 in 100 people. Keeping to a healthy weight can help to prevent it.

You'll usually have blood tests before starting olanzapine and while you're taking it to check your blood sugar.

If you already have diabetes you'll be monitored more closely and will have more regular blood sugar tests.

Taking olanzapine for a long time can sometimes affect your cholesterol. If this happens, your doctor may advise you to take a medicine to help lower your cholesterol.

Other side effects

These are not all the side effects of olanzapine. For a full list see the leaflet inside your medicines packet.

Reporting side effects

You can report any suspected side effect using the Yellow Card safety scheme.

Visit the Yellow Card website for more information about reporting side effects.

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