Droperidol is a drug in the neuroleptic drug class. It is administered as a preventive measure against nausea and vomiting after surgical procedures.
What is droperidol?
Droperidol is given as a preventive treatment for nausea and vomiting after surgical procedures. The drug droperidol belongs to a group called butyrophenones. Butyrophenones are a group of drugs used primarily in the pharmacological therapy of schizophrenia. Droperidol also has antipsychotic activity properties. In combination with the antiemetic effect, droperidol is therefore suitable as an agent against postoperative nausea and as a sedative in neuroanesthesia. The drug is a derivative of benperidol. At room temperature, droperidol is in white powder form. The powder is sparingly soluble in water. The drug is commercially available as a solution for injection. It has been approved in Switzerland since 2006. After being withdrawn from the market in 2001, the drug was also reapproved in Germany in 2008.
Pharmacologic action
Like most neuroleptics, droperidol has a binding affinity for D2 receptors in the central nervous system. D2 receptors are also called dopamine receptors. They serve as docking sites for dopamine, a neurotransmitter. Through the D2 receptors, dopamine has an inhibitory effect on the extrapyramidal motor system. Droperidol acts primarily on the D2 receptors in the area postrema. The area postrema is located in the brainstem and, together with the nucleus tractus solitarii, forms the vomiting center. The transmitter dopamine plays an important role in vomiting. Dopamine antagonists such as droperidol block the D2 receptors and thus lead to an inhibition of the urge to vomit. Droperidol also has a low affinity for D3 receptors. These receptors also serve as docking sites for dopamine. D3 receptors are found primarily in the limbic system and cortical areas of the brain. They play a role in emotional and cognitive processes. Inhibition of D3 receptors results in relief of psychotic symptoms. Droperidol can also bind to 5-HT2 receptors. Inhibition of receptor responsiveness has anxiolytic effects, among others.
Medicinal application and use
Droperidol was administered before surgical procedures along with the drug thalamonal until the 1980s. The combination of the active ingredients fentanyl] and droperidol was intended to sedate patients. At the same time, they were to be relieved of their fear of the surgical procedure. However, many of the patients complained of depression, panic and agitation accompanied by fatigue. For this reason, the drug was only used by anesthesiologists in exceptional cases. Benzodiazepines are now more commonly used for this purpose. In 2001, the peroral dosage form of droperidol was withdrawn from the market. Long-term high-dose therapy resulted in side effects that affected the heart. Along with the peroral form of administration, the parenteral form of administration was also withdrawn from the market. The drug was not approved again in Germany until 2008. Today, it is available in anesthesia for the prophylaxis and therapy of nausea and vomiting after surgery. It can be used in adults and in children over the age of two. Droperidol can also be administered to prevent nausea and vomiting caused by opioids during patient-controlled analgesia. Patient-controlled analgesia allows the patient to self-administer an analgesic. Classically, this involves intravenous administration of an opioid through a pain pump.
Risks and side effects
Droperidol should not be used in patients who have a known hypersensitivity or allergy to droperidol or to other ingredients of the medication. Hypersensitivity or allergy to butyrophenones are also contraindications. Droperidol must not be administered if there is a known or suspected prolonged QT time on the ECG. In women, the QT time must not exceed 440 ms; men must not exceed 450 ms. This restriction also applies to patients who have a family history of congenital prolonged QT time and to patients who contain drugs that have been shown to prolong QT time. Other contraindications to droperidol use include potassium deficiency and magnesium deficiency. Bradycardia, a slowed heartbeat, is also a contraindication.In patients with pheochromocytoma, another drug should also be used. Exclusion criteria also include comatose states, Parkinson’s disease, and major depression. Depressive episodes may occur when taking droperidol. Some patients also complain of nervousness, memory impairment, and confusion.
