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Overview: Weltruza is used to treat schizophrenia. It is thought to work by affecting certain chemicals in the brain. Common side effects include weight gain, sleepiness, headache, constipation, and reactions where the injection is given. Contact your health care provider right away or get emergency help if you have severe sleepiness, confusion, a high fever with stiff muscles, or a severe rash. Weltruza is given as a monthly injection under the skin by a health care provider.

Uses

What is Weltruza used for?

Weltruza (olanzapine) is commonly used to treat schizophrenia.

Weltruza may also be used for other conditions as determined by your health care provider.

How does Weltruza work (mechanism of action)?

Weltruza belongs to a group of medicines called atypical antipsychotics. It is thought to work by balancing brain chemicals called serotonin and dopamine. These chemicals are known to affect thoughts and mood.

How is Weltruza supplied (dosage forms)?

Brands and other names

  • Weltruza

Dosage forms and strengths

  • 318 mg, 425 mg, 531 mg long-acting injectable suspension

How should I store Weltruza?

Weltruza is given by a health care provider in a hospital or clinic. You will not store it at home.

Side Effects

What are the most common side effects of Weltruza?

The most common side effects of Weltruza are listed below. Tell your health care provider if you have any of these side effects that bother you.

  • Weight gain (see Metabolism Problems below)
  • Sleepiness
  • Headache
  • Constipation
  • Pain, redness or discoloration, itching, swelling, or hardness where the injection is given

There may be other side effects of Weltruza that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of Weltruza?

While less common, the most serious side effects of Weltruza are described below, along with what to do if they happen.

Severe Allergic Reactions. Weltruza may cause allergic reactions, including a serious specific type of allergic reaction called DRESS. DRESS stands for Drug Reaction with Eosinophilia and Systemic Symptoms. It is also sometimes called multi-organ hypersensitivity. This is a reaction that can affect multiple parts of the body including your liver, kidneys, and heart. Get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching or skin rash
  • Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Post-Injection Confusion or Drowsiness. When long-acting olanzapine is injected into the muscle, it may cause a serious reaction if too much of the medicine enters the blood too quickly. This type of reaction is called post-injection delirium/sedation syndrome (PDSS). Weltruza is injected under the skin, and it is not known whether this reaction can happen with Weltruza. Tell your health care provider right away if you have any of the following symptoms after your injection.

  • Unusual sleepiness
  • Dizziness, weakness, or trouble walking
  • Confusion
  • Feeling irritable, anxious, or nervous
  • Seizures

Neuroleptic Malignant Syndrome (NMS). Weltruza may cause a rare but serious condition called neuroleptic malignant syndrome, which may cause muscle stiffness and a high fever. Contact your health care provider right away if you experience any of the following symptoms.

  • High fever
  • Muscle stiffness or rigidity, where it is hard to move
  • Confusion 
  • Changes in your breathing or heart rate
  • Increased sweating

Metabolism Problems. Weltruza can cause or worsen high blood sugar levels or diabetes, high cholesterol levels, and weight gain. Keep all appointments with your health care provider to check your blood work and weight. Tell your health care provider if you gain weight or have the following symptoms of high blood sugar.

  • Thirsty more than usual
  • Peeing more than usual
  • Increase in hunger
  • Tiredness
  • Feeling sick to your stomach
  • Confusion
  • Your breath smelling fruity

Movement Problems. Weltruza may rarely cause movement problems that you cannot control in your face, tongue, or body, including shakiness, stiffness, or jerkiness. This condition is called tardive dyskinesia (TD). These movements may not go away, even after treatment stops. They may also start after you stop receiving Weltruza. Contact your health care provider right away if you notice any unusual or uncontrolled movements.

Low Blood Pressure Upon Standing (Orthostatic Hypotension) and Falls. Weltruza may cause a sudden drop in blood pressure when standing up from a seated or lying position. You may feel dizzy or lightheaded, have a fast or slow heartbeat, or faint. If you feel dizzy, sit or lie down right away until the dizziness stops, and be careful not to get up too quickly. Weltruza can also make you sleepy and slow your thinking and movements. These effects may lead to falls that cause broken bones or other injuries. Tell your health care provider if you feel dizzy or lightheaded, have a fast or slow heartbeat, or faint when you stand up.

Trouble Swallowing. Weltruza may make it hard for you to swallow liquids or food. This could make you more likely to get food or liquids into your lungs. Contact your health care provider if you have trouble swallowing.

Seizures. Weltruza may cause seizures. Your risk may be higher if you have had seizures in the past or have a condition that makes seizures more likely. Get help right away if you have a seizure or call your health care provider if you experience any of the following signs of a seizure.

  • Muscle twitching, jerking, spasms, tremors, or other uncontrolled movements
  • Stiffening of your arms and legs
  • Feeling anxious, nervous, confused, or a sense of dread
  • Feeling dizzy or lightheaded
  • Falling or losing consciousness

Decreased Alertness or Coordination. Weltruza can affect your alertness, thinking, or coordination. Do not drive or do other activities that require alertness or coordination until you know how Weltruza affects you.

Blood Disorders. Weltruza can cause blood disorders, including lowering your white blood cell counts. White blood cells help your body fight infections. Your health care provider may check your white blood cell counts during the first few months of treatment, especially if you have had low counts in the past. Keep all appointments to have your blood checked. Contact your health care provider right away if you have any of the following symptoms of blood disorders.

  • Fever
  • Shortness of breath
  • Pale or yellowish skin
  • Easy bruising or bleeding
  • Frequent infections
  • Unusual weakness or tiredness
  • Dizziness, lightheadedness, or feeling like you are about to pass out
  • Fast or abnormal heartbeat

Body Temperature Regulation. Weltruza can affect your ability to control your body temperature. This could make you become very hot, especially in hot weather or after exercising a lot. Drink plenty of water and avoid overheating and dehydration. Contact your health care provider right away if you are severely ill and have any of the following symptoms.

  • Excessive or no sweating
  • Dry mouth
  • Feeling very hot
  • Feeling thirsty 
  • Not able to pee

Excessive Prolactin (Hyperprolactinemia). Weltruza may increase the level of a hormone called prolactin in your blood. This may affect your fertility or cause bone loss over time. Contact your health care provider if you have any of the following symptoms.

  • Vaginal dryness 
  • Irregular or missed periods 
  • Production of breast milk when not pregnant or nursing 
  • Inability to get or keep an erection 
  • Enlarged breast size (gynecomastia) 
  • Decreased muscle and body hair

Warnings & Precautions

Who should not use Weltruza?

Allergies to Ingredients. People who are allergic to any of the following should not use Weltruza.

  • Olanzapine
  • Weltruza
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in Weltruza.

What should I know about Weltruza before using it?

Weltruza is given by a health care provider as an injection under the skin of your stomach area once a month. Do not inject Weltruza yourself.

Before you start Weltruza, your health care provider may have you take olanzapine by mouth to make sure you can tolerate it. When you switch from oral olanzapine, Weltruza is given the day after your last oral dose. Follow your health care provider's instructions about when to stop oral olanzapine.

Weltruza can affect your alertness or coordination. Do not drive or do other activities that require alertness or coordination until you know how Weltruza affects you.

Avoid getting too hot or dehydrated. In hot weather, stay inside in a cool place if possible, stay out of the sun, and avoid heavy clothing. Drink plenty of water.

Keep all appointments to have your weight, blood sugar, and blood fat levels checked. Your health care provider may also check your white blood cell counts.

Weltruza may make it hard for you to get pregnant. Contact your health care provider if you have concerns.

People who are 65 or older can be at greater risk of some side effects from Weltruza. Contact your health care provider about your risks if you are in this age group.

What should I tell my health care provider before using Weltruza?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if Weltruza is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. In particular, tell your health care provider if you have any of the following.

  • Diabetes or high blood sugar
  • High cholesterol or triglyceride levels, or low levels of good cholesterol
  • High or low blood pressure
  • Heart problems, stroke, or mini-stroke
  • Stroke or mini-stroke
  • Liver problems
  • Thoughts of suicide
  • Glaucoma
  • Dehydration
  • Low white blood cell counts
  • Seizures
  • Trouble peeing or prostate problems
  • Alzheimer's disease
  • Constipation or a blockage in your bowels
  • Breast cancer

Psychosis Related to Dementia. There is a higher risk of death, stroke, or mini-stroke in older adults who use Weltruza or another antipsychotic and have psychosis related to dementia. Weltruza is not approved to treat dementia-related psychosis.

Other Medicines and Supplements. Weltruza may interact with other medicines and supplements. Before starting Weltruza, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details. 

Pregnancy. Weltruza used later in pregnancy may cause abnormal muscle movements or withdrawal symptoms in your newborn. These may include agitation, stiff or floppy muscles, shaking, sleepiness, or breathing or feeding problems. Tell your health care provider if you are or plan to become pregnant while using Weltruza. Your health care provider will let you know if you should use Weltruza while you are pregnant or trying to get pregnant. 

A national registry is collecting safety information about the use of psychiatric medicines during pregnancy. If you become pregnant while using Weltruza, you can register by calling 866-961-2388 or online at www.womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry.

Breastfeeding. Weltruza passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed. Your health care provider will let you know if you should use Weltruza while breastfeeding. If you breastfeed during treatment, seek medical care if your baby is very sleepy, irritable, feeds poorly, or has shaking or abnormal muscle movements.

How can I get more information about Weltruza?

For more information about Weltruza, you can visit the drugmaker’s website at www.weltruza.com or call them at 888-483-8279.

Interactions

Does Weltruza interact with foods or drinks?

There are no known interactions between Weltruza and foods or nonalcoholic drinks.

Avoid drinking alcohol while using Weltruza. Drinking alcohol while using Weltruza could increase your risk of side effects, including sleepiness, dizziness, or fainting upon standing.

Does Weltruza interact with other medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before using Weltruza.

  • Carbamazepine, which is a medicine commonly used for seizures
  • Fluvoxamine, which is a medicine commonly used for mood disorders
  • Carbidopa/levodopa, which is a medicine used for movement disorders
  • A dopamine agonist, such as pramipexole (Mirapex) or ropinirole (Requip), which is a medicine commonly used for Parkinson’s disease, restless legs syndrome, and other conditions
  • A medicine for high blood pressure
  • An anticholinergic medicine, which includes antihistamines and medicines commonly used for overactive bladder, Parkinson’s disease, or stomach problems
  • Any other medicine that causes dizziness and sleepiness, such as prescription pain medicines, sleep medicines, and medicines for anxiety
  • Any other medicine that contains olanzapine

Some other medicines may alter the blood levels of Weltruza. Tell your health care provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with Weltruza. Always check with your health care provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much Weltruza?

If you or someone else has used too much Weltruza, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of Weltruza?

If you miss an appointment to get your Weltruza dose, contact your health care provider right away to make another appointment as soon as possible.

Weltruza can be given up to 1 week before or after your scheduled monthly dose. If more than 5 weeks have passed since your last injection, your health care provider should give your next dose as soon as possible. Your monthly schedule will then be adjusted based on the date you receive that dose.