Barhemsys is used alone or with other medications to prevent nausea and vomiting after a surgery.

Barhemsys may also be used for purposes not listed in this medication guide.

Before you are treated with Barhemsys, tell your doctor about all your medical conditions or allergies, all medicines you use, and if you are pregnant or breastfeeding.

Barhemsys is given as an infusion into a vein.

A healthcare provider will give you this injection while you are being prepared for surgery.

You should not be treated with Barhemsys if you are allergic to it.

Tell your doctor if you have ever had:

• a heart rhythm disorder;

• long QT syndrome (in you or a family member);

• congestive heart failure; or

• an electrolyte imbalance (such as low levels of potassium or magnesium in your blood).

Tell your doctor if you are pregnant or breastfeeding.

You should not breastfeed within 48 hours after receiving Barhemsys. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby.

Barhemsys is used as a single dose and does not have a daily dosing schedule.

Since Barhemsys is given by a healthcare professional in a medical setting, an overdose is unlikely to occur. However, overdose symptoms may include slow heartbeats, tremors, involuntary muscle movements, fainting, or seizure.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Barhemsys may cause serious side effects. Call your doctor at once if you have:

• sudden dizziness (like you might pass out);

• fast or pounding heartbeats, fluttering in your chest;

• shortness of breath; or

• low potassium level--leg cramps, constipation, irregular heartbeats, fluttering in your chest, increased thirst or urination, numbness or tingling, muscle weakness or limp feeling.

Common side effects of Barhemsys may include:

• low potassium;

• feeling light-headed;

• stomach bloating; or

• pain where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Barhemsys can cause a serious heart problem. Your risk may be higher if you also use certain other medicines for infections, asthma, heart problems, high blood pressure, depression, mental illness, cancer, malaria, or HIV.

Tell your doctor about all your other medicines you take for nausea or vomiting, especially droperidol or ondansetron.

Other drugs may affect Barhemsys, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.