Ketamine (brand name Ketalar) is a cyclohexanone derivative used for induction of anesthesia. Ketalar is indicated as the sole anesthetic agent for diagnostic and surgical procedures that do not require skeletal muscle relaxation; also, it is indicated for the induction of anesthesia prior to the administration of other general anesthetic agents. Ketamine blocks NMDA receptors through an interaction with sites thought to be located within the ion channel pore region. However, the complete pharmacology of ketamine is more complex, and it is known to directly interact with a variety of other sites to varying degrees. Recently, it was shown that inclusion of the NR3B subunit does not alter the ketamine sensitivity of recombinant NR1/NR2 receptors expressed in oocytes. Likewise, 100 μM ketamine produced only weak inhibition of the glycine-induced current of NR1/NR3A/NR3B receptors. The side effects of ketamine noted in clinical studies include psychedelic symptoms (hallucinations, memory defects, panic attacks), nausea/vomiting, somnolence, cardiovascular stimulation and, in a minority of patients, hepatoxicity. The recreational use of ketamine is increasing and comes with a variety of additional risks ranging from bladder and renal complications to persistent psychotypical behaviour and memory defects. Ketamine was first synthesized in 1962 by Calvin Stevens at Parke-Davis Co (now Pfizer) as an alternative anesthetic to phencyclidine. It was first used in humans in 1965 by Corssen and Domino and was introduced into clinical practice by 1970.

Esketamine is an S(+)-enantiomer of ketamine. It is a nonselective, noncompetitive antagonist of N-methyl-D-aspartate (NMDA) receptor. A nasal spray, containing esketamine, was approved in 2019 for the treatment of treatment-resistant depression in adults, in conjunction with an oral antidepressant, and is marketed under tradename SPARAVATO. Esketamine is a schedule III drug product in the USA.

Ketamine (brand name Ketalar) is a cyclohexanone derivative used for induction of anesthesia. Ketalar is indicated as the sole anesthetic agent for diagnostic and surgical procedures that do not require skeletal muscle relaxation; also, it is indicated for the induction of anesthesia prior to the administration of other general anesthetic agents. Ketamine blocks NMDA receptors through an interaction with sites thought to be located within the ion channel pore region. However, the complete pharmacology of ketamine is more complex, and it is known to directly interact with a variety of other sites to varying degrees. Recently, it was shown that inclusion of the NR3B subunit does not alter the ketamine sensitivity of recombinant NR1/NR2 receptors expressed in oocytes. Likewise, 100 μM ketamine produced only weak inhibition of the glycine-induced current of NR1/NR3A/NR3B receptors. The side effects of ketamine noted in clinical studies include psychedelic symptoms (hallucinations, memory defects, panic attacks), nausea/vomiting, somnolence, cardiovascular stimulation and, in a minority of patients, hepatoxicity. The recreational use of ketamine is increasing and comes with a variety of additional risks ranging from bladder and renal complications to persistent psychotypical behaviour and memory defects. Ketamine was first synthesized in 1962 by Calvin Stevens at Parke-Davis Co (now Pfizer) as an alternative anesthetic to phencyclidine. It was first used in humans in 1965 by Corssen and Domino and was introduced into clinical practice by 1970.

Ketamine (brand name Ketalar) is a cyclohexanone derivative used for induction of anesthesia. Ketalar is indicated as the sole anesthetic agent for diagnostic and surgical procedures that do not require skeletal muscle relaxation; also, it is indicated for the induction of anesthesia prior to the administration of other general anesthetic agents. Ketamine blocks NMDA receptors through an interaction with sites thought to be located within the ion channel pore region. However, the complete pharmacology of ketamine is more complex, and it is known to directly interact with a variety of other sites to varying degrees. Recently, it was shown that inclusion of the NR3B subunit does not alter the ketamine sensitivity of recombinant NR1/NR2 receptors expressed in oocytes. Likewise, 100 μM ketamine produced only weak inhibition of the glycine-induced current of NR1/NR3A/NR3B receptors. The side effects of ketamine noted in clinical studies include psychedelic symptoms (hallucinations, memory defects, panic attacks), nausea/vomiting, somnolence, cardiovascular stimulation and, in a minority of patients, hepatoxicity. The recreational use of ketamine is increasing and comes with a variety of additional risks ranging from bladder and renal complications to persistent psychotypical behaviour and memory defects. Ketamine was first synthesized in 1962 by Calvin Stevens at Parke-Davis Co (now Pfizer) as an alternative anesthetic to phencyclidine. It was first used in humans in 1965 by Corssen and Domino and was introduced into clinical practice by 1970.

Carbamazepine is an analgesic, anti-epileptic agent that is FDA approved for the treatment of epilepsy, trigeminal neuralgia. It appears to act by reducing polysynaptic responses and blocking the post-tetanic potentiation. It depresses thalamic potential and bulbar and polysynaptic reflexes, including the linguomandibular reflex in cats. Commonly reported side effects of carbamazepine include: dizziness, drowsiness, nausea, ataxia, and vomiting. Carbamazepine is a potent inducer of hepatic CYP1A2, 2B6, 2C9/19, and 3A4 and may reduce plasma concentrations of concomitant medications mainly metabolized by CYP1A2, 2B6, 2C9/19, and 3A4 through induction of their metabolism, like Boceprevir, Cyclophosphamide, Aripiprazole, Tacrolimus, Temsirolimus and others.

Droperidol produces marked tranquilization and sedation. It allays apprehension and provides a state of mental detachment and indifference while maintaining a state of reflex alertness. Droperidol produces an antiemetic effect as evidenced by the antagonism of apomorphine in dogs. It lowers the incidence of nausea and vomiting during surgical procedures and provides antiemetic protection in the postoperative period. Droperidol potentiates other CNS depressants. It produces mild alpha-adrenergic blockade, peripheral vascular dilatation and reduction of the pressor effect of epinephrine. It can produce hypotension and decreased peripheral vascular resistance and may decrease pulmonary arterial pressure (particularly if it is abnormally high). It may reduce the incidence of epinephrine-induced arrhythmias, but it does not prevent other cardiac arrhythmias. The exact mechanism of action is unknown, however, droperidol causes a CNS depression at subcortical levels of the brain, midbrain, and brainstem reticular formation. It may antagonize the actions of glutamic acid within the extrapyramidal system. It may also inhibit cathecolamine receptors and the reuptake of neurotransmiters and has strong central antidopaminergic action and weak central anticholinergic action. It can also produce ganglionic blockade and reduced affective response. The main actions seem to stem from its potent Dopamine (2) receptor antagonism with minor antagonistic effects on alpha-1 adrenergic receptors as well. Droperidol is used to produce tranquilization and to reduce the incidence of nausea and vomiting in surgical and diagnostic procedures.

Fentanyl is a potent agonist of mu opioid receptor. It is used to relieve severe pain, such as after surgery or during cancer treatment, and breakthrough pain (flare-ups of intense pain despite round-the-clock narcotic treatment). Fentanyl is an extremely powerful analgesic, 50–100-times more potent than morphine. Fentanyl harbors massive risk for addiction and abuse regardless of its prescription form. Fentanyl abuse is especially dangerous to those without a tolerance to opioids. The substance’s already elevated risk of overdose is multiplied when someone without a tolerance abuses it.

Fentanyl is a potent agonist of mu opioid receptor. It is used to relieve severe pain, such as after surgery or during cancer treatment, and breakthrough pain (flare-ups of intense pain despite round-the-clock narcotic treatment). Fentanyl is an extremely powerful analgesic, 50–100-times more potent than morphine. Fentanyl harbors massive risk for addiction and abuse regardless of its prescription form. Fentanyl abuse is especially dangerous to those without a tolerance to opioids. The substance’s already elevated risk of overdose is multiplied when someone without a tolerance abuses it.

Haloperidol is a phenyl-piperidinyl-butyrophenone that is used primarily to treat schizophrenia and other psychoses. It is also used in schizoaffective disorder, delusional disorders, ballism, and Tourette syndrome (a drug of choice) and occasionally as adjunctive therapy in mental retardation and the chorea of Huntington disease. It is a potent antiemetic and is used in the treatment of intractable hiccups. Haloperidol also exerts sedative and antiemetic activity. Haloperidol principal pharmacological effects are similar to those of piperazine-derivative phenothiazines. The drug has action at all levels of the central nervous system-primarily at subcortical levels-as well as on multiple organ systems. Haloperidol has strong antiadrenergic and weaker peripheral anticholinergic activity; ganglionic blocking action is relatively slight. It also possesses slight antihistaminic and antiserotonin activity. The precise mechanism whereby the therapeutic effects of haloperidol are produced is not known, but the drug appears to depress the CNS at the subcortical level of the brain, midbrain, and brain stem reticular formation. Haloperidol seems to inhibit the ascending reticular activating system of the brain stem (possibly through the caudate nucleus), thereby interrupting the impulse between the diencephalon and the cortex. The drug may antagonize the actions of glutamic acid within the extrapyramidal system, and inhibitions of catecholamine receptors may also contribute to haloperidol's mechanism of action. Haloperidol may also inhibit the reuptake of various neurotransmitters in the midbrain, and appears to have a strong central antidopaminergic and weak central anticholinergic activity. The drug produces catalepsy and inhibits spontaneous motor activity and conditioned avoidance behaviours in animals. The exact mechanism of antiemetic action of haloperidol has also not been fully determined, but the drug has been shown to directly affect the chemoreceptor trigger zone (CTZ) through the blocking of dopamine receptors in the CTZ. Haloperidol is marketed under the trade name Haldol among others.

Propranolol is a nonselective, beta-adrenergic receptor-blocking agent possessing no other autonomic nervous system activity. At dosages greater than required for beta blockade, propranolol also exerts a quinidine-like or anesthetic-like membrane action, which affects the cardiac action potential. Among the factors that may be involved in contributing to the antihypertensive action include: (1) decreased cardiac output, (2) inhibition of renin release by the kidneys, and (3) diminution of tonic sympathetic nerve outflow from vasomotor centers in the brain. Although total peripheral resistance may increase initially, it readjusts to or below the pretreatment level with chronic use of propranolol. Effects of propranolol on plasma volume appear to be minor and somewhat variable. In angina pectoris, propranolol generally reduces the oxygen requirement of the heart at any given level of effort by blocking the catecholamine-induced increases in the heart rate, systolic blood pressure, and the velocity and extent of myocardial contraction. Propranolol may increase oxygen requirements by increasing left ventricular fiber length, end diastolic pressure, and systolic ejection period. The net physiologic effect of beta-adrenergic blockade is usually advantageous and is manifested during exercise by delayed onset of pain and increased work capacity. Propranolol exerts its antiarrhythmic effects in concentrations associated with beta-adrenergic blockade, and this appears to be its principal antiarrhythmic mechanism of action. In dosages greater than required for beta blockade, propranolol also exerts a quinidine-like or anesthetic-like membrane action, which affects the cardiac action potential. The significance of the membrane action in the treatment of arrhythmias is uncertain. The mechanism of the anti-migraine effect of propranolol has not been established. Propranolol is indicated in the management of hypertension. It may be used alone or used in combination with other antihypertensive agents, particularly a thiazide diuretic. Also is indicated to decrease angina frequency and increase exercise tolerance in patients with angina pectoris; for the prophylaxis of common migraine headache. In addition, is used to improve NYHA functional class in symptomatic patients with hypertrophic subaortic stenosis. Due to the high penetration across the blood–brain barrier, propranolol causes sleep disturbances such as insomnia and vivid dreams, and nightmares. Dreaming (rapid eye movement sleep, REM) was reduced and increased awakening.