Amisulpride Injection

Amisulpride injection (brand name Barhemsys) is approved for adults in two specific situations related to surgery-related nausea and vomiting:

• Barhemsys — Prevention of PONV: Given at the time anesthesia is started to prevent postoperative nausea and vomiting, either alone or alongside another anti-nausea drug from a different class.
• Barhemsys — Treatment of PONV: Given after surgery if nausea or vomiting develops, in patients who either received no preventive anti-nausea medicine or received one from a different drug class.

Amisulpride selectively blocks dopamine D2 and D3 receptors in the brain — particularly in an area called the chemoreceptor trigger zone (CTZ), which acts as a relay station that detects certain chemicals in the blood and sends signals to the brain's vomiting center. By blocking dopamine from activating those receptors, amisulpride interrupts the chain of signals that would otherwise trigger nausea and vomiting. It has very little effect on other receptor types in the body, which helps keep its side-effect profile focused.

Barhemsys is given as a single intravenous (IV) infusion by a healthcare professional — no repeat dosing is part of the recommended regimen. For prevention of PONV, it is infused at the time anesthesia begins; for treatment of PONV, it is infused when nausea or vomiting occurs after surgery. Each infusion is given slowly over 1 to 2 minutes. Because this medicine is administered in a clinical setting, food and missed-dose guidance do not apply in the usual sense — your surgical team manages the timing entirely.

The most common side effects seen in clinical trials include:

More serious reactions — including dangerous heart rhythm changes, severe allergic reactions (such as swelling or hives), uncontrolled muscle movements, seizures, or a rare but life-threatening condition called neuroleptic malignant syndrome (high fever, muscle rigidity, confusion) — have been reported and require immediate medical attention.

• QT prolongation (heart-rhythm change): Barhemsys can lengthen the QT interval — part of the heart's electrical cycle — in a dose-dependent way. This can rarely lead to a dangerous arrhythmia called torsades de pointes. The risk is higher with faster infusion or higher doses than recommended. Avoid Barhemsys in patients with congenital long QT syndrome or those taking droperidol.
• Heart monitoring: An ECG (heart-rhythm tracing) is recommended for patients with pre-existing heart-rhythm problems, electrolyte abnormalities (low potassium or magnesium), heart failure, or those on other QT-prolonging medicines (such as ondansetron).
• Serious reactions from post-market data: Though based on chronic oral use outside the US (not the IV form), reported reactions include agranulocytosis (dangerous drop in white blood cells), severe heart-rhythm events, neuroleptic malignant syndrome, seizures, and severe allergic reactions. These are rare but serious.

Tell your surgical or anesthesia team about all medicines you take before receiving Barhemsys. Key interactions include:

• Droperidol: Avoid combining — both prolong the QT interval, which significantly raises the risk of a dangerous heart rhythm.
• Levodopa and dopamine agonists (e.g., Parkinson's medications): Barhemsys blocks dopamine receptors and can counteract the effects of these drugs; avoid using together.
• Ondansetron and other QT-prolonging drugs: Heart-rhythm monitoring is recommended when Barhemsys is used alongside medicines that also affect the QT interval.
• MATE1 and MATE2-K transporter substrates: Amisulpride inhibits these kidney transporters in lab studies, which could theoretically affect how certain other drugs are cleared — though no clinical drug interaction trials have been conducted with Barhemsys.

Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.

• Allergy: Do not receive Barhemsys if you have a known allergy to amisulpride.
• Congenital long QT syndrome: Barhemsys must be avoided if you have this inherited heart-rhythm condition.
• Heart or electrolyte problems: Tell your care team if you have heart-rhythm disorders, low potassium or magnesium, or heart failure — ECG monitoring will be needed.
• Pregnancy: Human data are too limited to fully assess the risk; discuss with your doctor if you are pregnant.
• Breastfeeding: Amisulpride passes into breast milk. Consider pumping and discarding milk for 48 hours after receiving Barhemsys to reduce your infant's exposure.
• Fertility: Animal studies showed reversible infertility in female rats with repeated dosing; the relevance to a single human IV dose is not established.
• Children: Safety and effectiveness have not been established in pediatric patients.
• Older adults (65+): No major differences in safety or effectiveness were seen in clinical trials, but individual sensitivity may vary.
• Kidney impairment: Dose adjustments are not considered necessary for mild, moderate, or severe kidney impairment, as the pharmacokinetic changes are not clinically meaningful for a single dose.

Overdose information is based on high-dose oral amisulpride use (Barhemsys is not approved for oral use). Excessive amounts can cause heart problems — such as QT prolongation, dangerous heart rhythms, and low blood pressure — as well as neurological effects like sedation, seizures, and uncontrolled muscle movements. There is no specific antidote; treatment focuses on heart monitoring and managing severe muscle or movement symptoms. Hemodialysis (kidney-filtering treatment) is not effective at removing this drug.

Barhemsys affects the heart's electrical system in a dose- and concentration-dependent way, measurably lengthening the QT interval — the time it takes for the heart's lower chambers to reset between beats. At the recommended doses (given slowly over 1 to 2 minutes), the effect on QT interval is small. At higher doses or faster infusion rates, the effect is substantially larger, which is why the infusion rate and dose limits are strictly defined.

When given intravenously, amisulpride reaches its peak blood concentration immediately at the end of the infusion, then drops to about half that level within roughly 15 minutes. It is not significantly broken down by the liver's main enzyme systems (cytochrome P450 enzymes), and the majority of the drug leaves the body unchanged through the urine. The elimination half-life — the time it takes for the body to clear half the drug — is approximately 4 to 5 hours. Kidney function affects how quickly the drug is cleared, but even in patients with significant kidney impairment, the difference is not considered clinically meaningful for a single dose.

Store vials at 20°C to 25°C (68°F to 77°F) . Protect from light.