Droperidol injection

It is employed basieally as an analgesie for the control of pain associated with all kinds of surgery. It may also be used an an adjunet to all drugs eommonly employed for regional and general anaesthesia. It is one of the eomponents in Fentanyl citrate and Droperidol Injection which is used as premedication for anaesthesia and also as an supplement for induction and maintenance of anaesthesia. 

Oral 2, 5, 10 mg tablets 5 mg/5 mL and 5 mg/mL solution Oral sustained-release 15 mg capsules Parenteral 5 mg/mL for injection Droperidol (generic, Inapsine)... 

Flaloperidol is available both in an injectable form and in oral dosage form. The principal exposure pathway is intentional ingestion by adults or accidental ingestion by small children. Pharmacists, physicians, and nurses dispensing or administering haloperidol could be exposed through dermal contact. Droperidol is available only as an injectable drug. The most common route of exposure is an accidental injection. 

Flaloperidol is well absorbed orally with a bioavailability of 60-65% due to first-pass hepatic metabolism. It has a reversible oxidation/reduction metabolic pathway it is metabolized via reduction to reduced haloperidol, which is biologically inactive. Both agents are rapidly absorbed after intramuscular injection, peaking within 10 min. Butyrophenones are metabolized in the liver to inactive metabolites. Concentrations of butyrophenones are found in the liver, central nervous system, and throughout the body. Flaloperidol is 92% protein bound. Haloperidol is 15% eliminated through the bile. The elimination half-life is 14-41 h. The half-life of droperidol is 2 h 10% is recovered unchanged in the urine. 

Droperidol is used as an adjunct for induction and maintenance of general anesthesia and as an anesthetic in diagnostic procedures. Droperidol, which has antiemetic properties, causes marked sedation and potentiates the CNS depressant effects of alcohol, hypnotic-sedatives, and numerous psychoactive agents. Droperidol is absorbed well through an IM injection—sedation begins in 3 minutes, peaks at 30 minutes, and lasts for 2 to 4 hours. Droperidol is metabolized by the liver to p-fluoro-phenylacetic acid and p-hydroxypiperidine, and its metabolites are excreted in urine and feces. 

Haloperidol was introduced for the treatment of psychoses in Europe in 1958 and in the United States in 1967 (Fig. 22.7). it is an effective aiternative to more famiiiar antipsychotic phenothiazine drugs and also is used for the manic phase of bipolar (manic-depressive) disorder. Haloperidol decanoate has been introduced as depot maintenance therapy. When injected every 4 to 6 weeks, the drug appears to be as effective as daily orally administered haloperidol. Other currently available (mostly in Europe) butyrophenones include the very potent spiperone (spiroperidol) as well as trifluperidol and droperidol. Droperidol, a short-acting, sedating butyrophenone, is used in anesthesia for its sedating and antiemetic effects and, sometimes, in psychiatric emergencies as a sedative-neuroleptic. Droperidol often is administered in combination with the potent narcotic analgesic fentanyl for preanesthetic sedation and anesthesia. 

The structure of fentanyl and related compounds are given in Table 24.4. Fentanyl is a p agonist with approximately 80 times greater potency than morphine. Fentanyl has been used in combination with nitrous oxide for balanced anesthesia and in combination with droperidol for neurolepalgesia. The advantages of fentanyl over morphine for anesthetic procedures are its shorter duration of action (1-2 hours) and the fact that it does not cause histamine release on intravenous injection. 

The effects of fentanyl and droperidol with fentanyl in depressing respiration were studied in 29 subjects undergoing nitrous oxide anaesthesia. The combination of the drugs used was the proprietary preparation Innovar containing fentanyl 0.05 mg/ml and droperidol 2.5 mg/ml. In the study patients received fentanyl, alone or as Tn-novar , 1.5 pg/kg by intramuscular injections... 

Both fentanyl and Innovar depressed the slope of the rebreathing carbon dioxide response curve to 42% 6 of the values obtained in the same subjects when awake. After the last injection of fentanyl or the fentanyl/droperidol combination the slope of the curve increased to 77% 8 of the control level but after reaching a normal level the respiratory depression recurred, the slope of the curve falling to 55% + 5 of the control value. Subsequently the slope of the curve returned to near normal levels. 

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