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PubMed1988

Reversals of the neostigmine-induced tetanic fade and endplate potential run-down with respect to the autoregulation of transmitter release.

1. In order to shed more light on the role of presynaptic cholinoceptors in the modulation of transmitter release, the effects of tubocurarine, choline and hexamethonium on neostigmine-induced tetanic fade and run-down of endplate potentials (e.p.ps) in response to indirect stimulation with trains of pulses were studied in the intact and cut isolated phrenic nerve-diaphragm preparation of the mouse, respectively. 2. Tubocurarine, choline and hexamethonium reduced both the tetanic fade and e.p.p. run-down caused by neostigmine, despite the fact that they themselves also induced these two effects. 3. At a given degree of postsynaptic inhibition, choline and hexamethonium caused less e.p.p. run-down and reversed the neostigmine-induced tetanic fade and e.p.p. run-down better than tubocurarine. Moreover, the e.p.p. run-down caused by choline or hexamethonium, but not that induced by tubocurarine, was reciprocally reversed by neostigmine. 4. Tubocurarine, choline and hexamethonium significantly decreased the endplate depolarization induced by repetitive nerve stimulation in the presence of neostigmine. The remaining depolarization continued to grow during repetitive stimulation in the presence of choline or hexamethonium, but not, however, in the presence of tubocurarine; a finding which suggests that choline and hexamethonium but not tubocurarine may be displaced from the receptor by the accumulated acetylcholine. 5. The mutual reversal by neostigmine and cholinoceptor antagonists of e.p.p. run-down may implicate the presence of a positive (physiological) and a negative (pharmacological) feedback regulation for evoked transmitter release via nicotinic cholinoceptors in the mammalian motor nerve, depending on the concentration of acetylcholine within the synaptic cleft.

Animals↗
PubMed2006

The neurotoxic effects of intrathecal midazolam and neostigmine in rabbits.

In parallel with improvements in understanding pain neurophysiology, many chemicals have recently been investigated for spinal anaesthesia and analgesia. However, studies discussing the effects of these drugs on neural tissue indicate that knowledge about some aspects of neurotoxicity is limited. Forty-nine New Zealand albino rabbits, weighing 2.2 +/- 0.2 kg, were randomly assigned to seven groups of seven animals each. Single dose groups received intrathecally through the atlantooccipital membrane 0.9% saline 1.5 ml; midazolam 100 microg/kg (low dose midazolam group) or 500 microg/kg (high dose midazolam group); neostigmine 10 microg/kg (low dose neostigmine group) or 50 microg/kg (high dose neostigmine group). Two groups had seven days of repeated dosing with either midazolam 100 microg/kg/day (repeat midazolam group) or 10 microg/kg/day neostigmine (repeat neostigmine group). The animals were sacrificed on day 8, and two spinal cord sections from the fourth cervical level and fourth lumbar level were removed and prepared for histopathological study. Transmission electron microscopic evaluations were performed on transverse spinal cord sections by a neuropathologist blinded to the group allocation. Twenty myelinated axons and neurones in the cervical and lumbar sections were investigated for the histopathological study. This study indicates that midazolam and neostigmine have different neurotoxic effects that depend on the dose and the repetition of dosing when these drugs are administered intrathecally.

Analysis of Variance↗
PubMedDate not supplied

The effects of bupivacaine and neostigmine on articular cartilage and synovium in the rabbit knee joint.

We investigated the effects of intra-articular injections of bupivacaine and neostigmine on articular cartilage and the synovial membrane of rabbit knee joints. Saline, bupivacaine or neostigmine were each administered intra-articularly into 15 knee joints. Five joints per drug treatment were prepared for histopathological examination 24 h, 48 h and 10 days after injection. A pathologist examined the histological samples for inflammation of the articular cartilage, inflammatory cell infiltration, hypertrophy and hyperplasia of the synovial membrane, in a blinded manner. There no histopathological in the saline-treated control joints. Joints treated with bupivacaine and neostigmine showed significantly more histopathological changes than control joints. Joints treated with neostigmine showed significantly more histopathological changes than those treated with bupivacaine, except for articular cartilage inflammation on day 10. We conclude that intra-articular bupivacaine and neostigmine cause histopathological changes in rabbit knee joints, with neostigmine having a greater effect than bupivacaine.

Anesthetics, Local↗
PubMedDate not supplied

Antagonism of pancuronium and its metabolites by neostigmine in cats.

Antagonism by neostigmine of neuromuscular blockade produced by pancuronium or its metabolites was studied in the cat anterior or tibialis muscle-peroneal nerve preparation using constant infusions of muscle relaxants. The ED50 of neostigmine (dose which caused a 50% antagonism) was 16, 11, 29, and 26 micrograms/kg for pancuronium, 3-hydroxypancuronium, 17-hydroxypancuronium, and 3, 17-hydroxypancuronium, respectively. Times of onset of neostigmine action were shorter when antagonizing 17-hydroxypancuronium neuromuscular blockade. Duration of neostigmine action when antagonizing 17- or 3, 17-hydroxypancuronium blockade was shorter than with pancuronium or 3-hydroxypancuronium. We conclude that more neostigmine is required to antagonize 17- or 3,17-hydroxypancuronium neuromuscular blockade than is required to antagonize pancuronium. Conversely, less neostigmine was required to antagonize 3-hydroxypancuronium blockade.

Animals↗
PubMed2003

The effect of epidural neostigmine combined with ropivacaine and sufentanil on neuraxial analgesia during labor.

UNLABELLED: Spinal neostigmine produces analgesia without respiratory depression or hypotension but provokes major gastrointestinal side effects. Epidural injection of this drug, however, appears to induce analgesia devoid of such side effects. In this study, we evaluated the effect of a bolus of epidural neostigmine on the duration and magnitude of analgesia in early labor and assessed its eventual sparing effect on subsequent local anesthetic requirements. Epidural neostigmine methylsulfate (maximal dose 4 microg/kg) was added to 10 mL of ropivacaine 0.1%, with and without sufentanil 10 microg, to initiate analgesia. Twenty minutes after injection, pain score, sensory level, and motor block were assessed. Time until request for supplemental epidural medication was also recorded. Patient-controlled epidural analgesia with ropivacaine 0.1% was used for epidural supplementation. Maternal and fetal side effects were closely recorded. Neostigmine (4 microg/kg), when added to ropivacaine 10 mg, provided equivalent analgesia to ropivacaine 20 mg but was less effective than sufentanil 10 microg for the initiation of labor epidural analgesia. Further, neostigmine did not modify the subsequent patient-controlled epidural analgesia local anesthetic requirements during labor. No hemodynamic instability, additional motor block, or bothersome side effects were recorded. IMPLICATIONS: The combination of epidural neostigmine (4 microg/kg) with the local anesthetic ropivacaine, with or without sufentanil, does not significantly enhance neuraxial analgesia during labor. Such a dose, however, has no bothersome side effects.

Adult↗
PubMed1997

Antinociceptive effect of intrathecal neostigmine evaluated in rats by two different pain models.

The analgesic efficacy of cholinergic agonists and anticholinesterase agents has been widely recognized. The analgesic effect obtained by activating cholinergic mechanisms, however, seems to depend on the experimental pain model utilized for its evaluation. The antinociceptive effect of intraspinal neostigmine was examined in rats submitted concurrently to the tail flick and formalin tests. Neostigmine (8.25 and 16.5 nmol) produced a dose-dependent antinociceptive effect in the tail flick test (a model of phasic pain) and reduced the first phase (phasic pain) of the animal response to formalin also in a dose-dependent manner. The second phase (tonic pain) of the response to formalin, however, was slightly reduced after a longer period of time only by the higher dose of the anticholinesterase. The effect of neostigmine was not significantly different when the drug was injected into rats submitted exclusively to the tail flick test. The second phase of the animal response to formalin was slightly reduced by neostigmine (8.25 nmol) and strongly inhibited by the higher dose of the anticholinesterase when injection was made after the first phase. We conclude that phasic and tonic pain can both be controlled by high doses of neostigmine. In addition, we show that inhibition by a lower dose of neostigmine of the formalin-induced phasic pain did not prevent the subsequent occurrence of tonic pain produced by the irritant.

Animals↗
PubMed1975

Central cholinergic control of cerebral blood flow in the baboon. Effect of cholinesterase inhibition with neostigmine on autoregulation and CO2 responsiveness.

Cerebral autoregulation and vastomotor responsiveness to carbon dioxide (CO2) were measured quantitatively by the use of the autoregulation index and chemical index, respectively, in normal baboons before and after intravertebral and intracarotid infusion of the anticholinesterase agent, neostigmine methylsufate (Prostigmin). Continuous measurements were made of cerebral blood flow (measured as bilateral internal jugular venous outflow), arterial and cerebral venous pO2 and pCO2, cerebral arteriovenous oxygen differences, and endotracheal CO2. The effect of intravertebral infusion of neostigmine (12.5 mug/kg body weight) was compared to intravertebral infusion of neostigmine (25 mug/kg body weight) for assessment of any specific action of the drug on a hypothetical cholinergic vasomotor center, presumed to be located in the territory of the vertebrobasilar supply. No significant or persistent changes in cerebral blood flow (CBF) and cerebral metabolic rate for oxygen (CMRO2) followed either intravertebral or intracarotid infusion of neostigmine. Cerebral vascular resistance (CVR) and cerebral perfusion pressure (CPP), however, decreased significantly after intravertebral infusion. Cerebral autoregulatory vasoconstriction during increases of CCP was significantly reduced following both intravertebral and intracarotid infusion. Cerebral autoregulatory vasodilatation was not altered as CPP was lowered. Cerebral vasodilatory reactivity to CO2 inhalation was significantly enhanced following intravertebral neostigime but not following intracarotid neostigmine. Cerebral vasoconstrictive response to hyperventilation was not influenced by neostigmine. These results support the view that central cholinergic cerebrovascular influences exist, and are vasodilatory in nature.

Acetylcholine↗
PubMed2001

Synergistic effects between intrathecal clonidine and neostigmine in the formalin test.

Spinal alpha-2 adrenoceptors and cholinergic receptors are involved in the regulation of acute nociception and the facilitated processing. The aim of this study was to examine the pharmacological effect of an intrathecal alpha-2 agonist and a cholinesterase inhibitor on the facilitated pain model induced by formalin injection and to determine the nature of drug interaction using an isobolographic analysis. Both intrathecal clonidine and neostigmine dose-dependently suppressed the flinching during phase 1 and phase 2. Intrathecal pretreatment with atropine reversed the antinociceptive effects of clonidine and neostigmine in both phases. Pretreatment with intrathecal yohimbine attenuated the effect of clonidine. The antinociception of clonidine and neostigmine was not reversed by mecamylamine. Isobolographic analysis showed that intrathecal clonidine and neostigmine acted synergistically in both phase 1 and 2. Intrathecal pretreatment with atropine and yohimbine antagonized the effect of the mixture of clonidine and neostigmine in both phases, but no antagonism was observed with mecamylamine pretreatment. These data indicate that spinal clonidine and neostigmine are effective to counteract the facilitated state evoked formalin stimulus, and these two drugs interact in a synergistic fashion. In addition, the analgesic action of intrathecal clonidine is mediated by spinal muscarinic receptors as well as alpha-2 adrenoceptors.

Adrenergic alpha-Agonists↗
PubMed2001

A multicenter evaluation of the time-course of action of two doses of rapacuronium after early and late reversal with neostigmine.

UNLABELLED: Early reversal of rapacuronium may accelerate return of neuromuscular function. This study was designed to compare early (2 min after rapacuronium) or late (at 25% recovery of the first twitch [T1] of train-of-four) reversal of rapacuronium with neostigmine. We studied 119 subjects between the ages of 18 and 75 yr. Anesthesia was induced with fentanyl and thiopental and maintained with nitrous oxide, propofol, and fentanyl. Mechanomyographic neuromuscular monitoring was performed by using train-of-four stimulation of the ulnar nerve. Two groups received 1.5 mg/kg rapacuronium followed by neostigmine (50 microg/kg) and glycopyrrolate (10 microg/kg) either at 2 min after rapacuronium bolus or at 25% T1 recovery. The other two groups received 2.0 mg/kg rapacuronium, after which neostigmine was similarly given. For each rapacuronium dose, the time from the administration of rapacuronium to the start of T1 recovery or 25% T1 recovery was significantly shorter in subjects who received the reversal 2 min after rapacuronium. However, late recovery, defined by times from administration of rapacuronium to 70%, or 80% T4/T1 recovery, was not influenced by early reversal administration. We conclude that initial recovery is accelerated by early administration of neostigmine. Time to full recovery after rapacuronium administration is, however, dose-dependent and not significantly altered by early administration of neostigmine. IMPLICATIONS: "Rescue reversal," which includes the administration of neostigmine shortly after the administration of rapacuronium, may accelerate the return of spontaneous breathing (early recovery), but does not shorten the time to complete recovery of upper airway function.

Adolescent↗
PubMed1975

The effect of temperature on a d-tubocurarine neuromuscular blockade and its antagonism by neostigmine.

In 19 cats anesthetized with chloralose and urethrane, d-tubocurarine (d-TC) was continuously infused to produce constant 90% depression of twitch tension prior to injection of 5, 10 or 20 mug/kg of neostigmine. The required mean infusion rates of d-TC were 3.6 +/- 0.6, 5.1 +/- 0.3, 8.5 +/- 0.3 and 8.9 +/- 0.5 mug/kg/min at body and muscle temperatures of 28, 31, 37 and 41 degrees C, respectively. The doses of neostigmine needed for 50% antagonism of the d-TC-induced depression of twitch height were 8.7, 9.2, 10.5 and 12.0 mug/kg at 28, 31, 37 and 41 degrees, respectively. The time to peak effect and duration of action of 5 and 10 mug/kg of neostigmine were longer at 28 and 31 degrees C than at 37 and 41 degrees C. Although these times also were longer at 27 and 31 degrees C with the 20 mug/kg dose of neostigmine, they were not statistically different. We conclude that hypothermia augments a d-TC neuromuscular blockade. Hypothermia prolongs time-to-peak effect and duration of neostigmine but does not affect peak magnitude of antagonism of d-TC by neostigmine.

Animals↗
PubMed2000

Effects of neostigmine on the pharmacokinetics of intravenous parathion in rats.

It was reported that the area under the plasma concentration-time curve from time zero to time infinity (AUC) of parathion was significantly smaller and the time-averaged total body clearance (CL) of parathion was significantly faster after intravenous administration of parathion to rats pretreated with dexamethasone than those in control rats. This was supported by significantly faster intrinsic clearance of parathion to form paraoxon in hepatic microsomal fraction of rats pretreated with dexamethasone. The above data suggested that parathion was metabolized to paraoxon by dexamethasone-inducible hepatic cytochrome P450 (CYP) 3A in rats. The purpose of this study is to explain the protective effects of neostigmine against paraoxon toxicity by suppressing CYP3A and hence decreasing formation of toxic metabolite, paraoxon by neostigmine. The pharmacokinetic changes of parathion and its active metabolite, paraoxon, were investigated after intravenous administration of parathion, 3 mg/kg, to control Sprague-Dawley rats and the rats pretreated with neostigmine (200 microg/kg, intraperitoneal injection 30 min before parathion administration). After 1-min intravenous infusion of parathion to rats pretreated with neostigmine, the AUC of parathion (65.1 versus 74.3 microg min/ml) was significantly greater and the CL of parathion (45.1 versus 40.4 ml/min/kg) was significantly slower than those in control rats. Based on in vitro hepatic microsomal studies, neostigmine inhibited significantly the erythromycin N-demethylase activity (1.03 versus 0.871 nmol/mg protein/min), mainly mediated by hepatic cytochrome P450 3A in rats. The above data suggested that the formation of paraoxon was inhibited in rats pretreated with neostigmine by inhibiting CYP3A.

Animals↗
PubMed2002

Can neostigmine reduce propofol injection pain?

BACKGROUND: Neostigmine has been found to cause peripheral analgesia. We used venous retention technique to evaluate whether neostigmine displayed peripheral analgesic effect in reducing propofol injection pain. METHODS: In a double blind fashion, 105 patients were randomly allocated to receive either 1 ml 0.5 mg neostigmine (Group N, n = 35), 1 ml 2% lidocaine (Group L, n = 35), or 1 ml normal saline (Group C, n = 35) as pretreatment to reduce pain on propofol injection. A pediatric T-connector linking with the i.v. catheter port was used for injection. Venous occlusion was made possible with a tourniquet before the intravenous administration of one of the three drugs. The tested drug was allowed to retain for one minute and then the tourniquet was released for propofol injection. Pain and side effect assessments were made after propofol injection. RESULTS: The incidence of propofol injection pain was 85% in normal saline group, 46% in neostigmine group and 6% in lidocaine group (P < 0.05 among groups). The tested drugs arrayed in order of increasing magnitude of intensity of pain upon propofol injection were lidocaine (mean rank 34.20), neostigmine (mean rank 50.42) and normal saline (mean rank 76.81) in sequence (P < 0.05 among groups). CONCLUSIONS: With one-minute venous retention, 0.5 mg neostigmine (1 ml) could produce peripheral analgesia to some degree in reducing propofol injection pain. However, its analgesic effect was inferior to 1 ml of 2% lidocaine.

Adolescent↗
PubMed2005

[Effect of neostigmine on atracurium-induced neuromuscular blockage in patients pretreated with magnesium sulphate].

OBJECTIVE: To determine the effect of neostigmine on antagonizing atracurium-induced neuromuscular blockage with sulfate magnesium pretreatment. METHODS: Forty patients who undertook elective gynecologic laparoscopic examinations and treatments under general anesthesia were randomized into four groups (group A, B, C, and D, group A paired with group C, and group B paired with group D). Before induction of general anesthesia, patients in group A and group C received MgSO4 30 mg/kg in saline intravenously within 5 min, while patients in group B and group D received the same volume of saline. Anesthesia was induced with fentanyl and propofol; subsequently tracheal intubation was performed with 0.5 mg/kg atracurium after stabilization of the electromyography recording, and neostigmine (0.02 mg/kg) and atropine (0.01 mg/kg) were infused in group C and group D when neuromuscular recovery (T1/T(C)) reached 10%. T1/T(C) changes after neostigmine infusion as well as haemodynamic changes and other responses during induction and neostigmine and atropine infusion were recorded. RESULTS: The neuromuscular recovery speed had no significant difference between group A and group B after the neuromuscular recovery reached 10%, but it was lower in group C than in group D (P < 0.05). Significant difference existed between group AC and group BD (P < 0.05). No haemodynamic changes and other responses were found during induction and neostigmine and atropine infusion. CONCLUSION: Neostigmine-induced neuromuscular recovery can be attenuated in patients pretreated with magnesium sulfate.

Adolescent↗
PubMed1989

Dose-response relationships for edrophonium and neostigmine as antagonists of moderate and profound atracurium blockade.

To measure the ability of neostigmine and edrophonium to reverse moderate and profound atracurium blockade, dose-response relationships were established for these reversal agents given at 1% and 10% twitch height recovery. Eighty-five ASA I and II adult patients received atracurium, 0.4 mg/kg, during a thiopental-nitrous oxide-enflurane anesthetic. Train-of-four stimulation was applied every 12 seconds, and the force of contraction of the adductor pollicis muscle was recorded. Edrophonium, 0.1, 0.2, 0.4, or 1 mg/kg; neostigmine, 0.005, 0.01, 0.02 or 0.05 mg/kg; or no reversal agent was given when there was either 1% or 10% recovery of the first twitch response. With profound blockade, the slope of the edrophonium dose-response relationship was significantly flatter (P less than 0.05) than that of neostigmine. The dose of neostigmine required to achieve 80% first twitch recovery (ED80) after 10 minutes was 0.013 +/- 0.003 mg/kg (mean +/- SEM) if given at 10% recovery, and 0.032 +/- 0.004 mg/kg if given at 1% recovery. The ED80 for edrophonium was 0.22 +/- 0.04 mg/kg and 1.14 +/- 0.33 mg/kg, respectively. These values corresponded to neostigmine:edrophonium potency ratios of 16.6 +/- 3.5 and 35.3 +/- 8.9 at 90% and 99% blockade respectively (P less than 0.006). We conclude that the relative potency of neostigmine is greater than that of edrophonium for antagonism of profound atracurium blockade.

Atracurium↗
PubMed1978

Neostigmine-induced alterations at the mammalian neuromuscular junction. II. Ultrastructure.

Brief and chronic exposure of rats to neostigmine methylsulfate produced marked morphological alterations of the fine structure at the end-plate region of the extensor digitorum longus muscles. These changes were dose and time dependent and were restricted primarily to the subjunctional myofibrillar apparatus and membrane-bound organelles. In addition, significant presynaptic alterations were observed including synaptic vesicle depletion and the appearance of numerous coated vesicles and membrane cisternae, which indicated continuing nerve terminal hyperactivity. With chronic treatment, degeneration and partial recovery of the nerve axon also were observed. The morphological changes of the end-plate region induced by neostigmine did not occur in most fibers after brief denervation and were eliminated entirely by chronic nerve section. Thus, the postsynaptic degenerative changes caused by neostigmine treatment observed in nondenervated animals appear to result primarily from greatly increased synaptic activity and not primarily from a direct neostigmine reaction with the pre- or postsynaptic membranes. Since the myopathic changes observed in this study were produced by neostigmine, a drug which is commonly employed in the routine treatment of human patients with myasthenia gravis, continued use of neostigmine for long-term therapy in noncrisis situations may not be accepted as being free from risk.

Animals↗
PubMed1984

Antagonism of pancuronium neuromuscular blockade in halothane-anesthetized ponies using neostigmine and edrophonium.

Efficacy of neostigmine (0.04 mg/kg of body weight) and edrophonium (1 mg/kg), as antagonists for pancuronium neuromuscular blockade in halothane-anesthetized ponies, was evaluated. Neostigmine and edrophonium were satisfactory antagonists, with edrophonium having a significantly (P less than 0.01) more rapid onset of action than did neostigmine. Muscarinic activity of neostigmine and edrophonium was also evaluated. Neither antagonist was administered with atropine. Gastrointestinal effects, increased salivation, and increased airway secretions were minimal with edrophonium, but were marked after neostigmine. Blood pressure increased within 1 to 2 minutes of antagonist administration. Heart rate decreased after edrophonium injection, but this occurred after blood pressure increase. Heart rate increased or did not change after neostigmine administration.

Anesthesia, General↗
PubMed1995

Effect of bethanechol, neostigmine, metoclopramide, and propranolol on myoelectric activity of the ileocecocolic area in cows.

The effect of bethanechol, neostigmine, metoclopramide, and propranolol on myoelectric activity of the ileum, cecum, and proximal loop of the ascending colon was determined in 6 healthy Jersey cows implanted with 8 pairs of bipolar electrodes. Assigned at random, each cow received each of 5 treatments in 3-day intervals. The treatments included bethanechol (0.07 mg/kg of body weight, SC), neostigmine (0.02 mg/kg, SC), metoclopramide (0.15 mg/kg, IM), DL-propranolol (0.2 mg/kg, IM), and 0.9% sodium chloride (NaCl) solution (20 ml, SC). All drugs were administered during early phase I of the migrating myoelectric complex in the ileum. Myoelectric activity was recorded for 4 hours after treatment, and data were analyzed for each hour separately. Bethanechol and neostigmine significantly (P < 0.05) increased the number of cecocolic spikes per minute per electrode, duration of cecocolic spike activity (%), and number of cecocolic propagated spike sequences per 10 minutes, relative to NaCl, during 1 or more hours of the recording period. The effect of bethanechol was more pronounced on duration of spike activity and number of propagated spike sequences, whereas neostigmine mainly increased the number of (uncoordinated) spikes. Metoclopramide and propranolol had no significant effect on cecocolic myoelectric activity, relative to NaCl. It was concluded that bethanechol and, less likely, neostigmine at the dosage used in this study may be suitable for medical treatment of cecal dilatation in cattle in which hypomotility of the cecum and proximal loop of the ascending colon has to be reversed. The potential advantage of bethanechol vs neostigmine for medical treatment of cecal dilatation is worth further evaluation.

Adrenergic beta-Antagonists↗
PubMed1995

Optimum time for neostigmine administration to antagonize vecuronium-induced neuromuscular blockade.

We followed the recovery time course in 46 patients antagonized by neostigmine (0.036 mg kg-1) at different levels of vecuronium-induced neuromuscular blockade ranging from post-tetanic count 1 to train-of-four ratio 0.4 and in 15 patients during spontaneous recovery. Non-linear regression curve fit analyses showed that the optimal time for neostigmine administration was when the first twitch in the train of four (T1) was between 1% and 10%. Visual analyses of the scattergram in which the level of block, when neostigmine was given, was plotted against total recovery time (the time elapsed from administration of the last dose of vecuronium to train-of-four ratio 0.7) gave the same result. The reduction in total recovery time achieved by neostigmine was 32.6 min (SE diff. 6.0 min). To achieve the optimum effect, neostigmine must therefore be given 32.6 min plus the required time for peak effect of neostigmine (5.3-7.1 min), i.e. 37.9-39.7 min, before train-of-four ratio 0.7 is reached. During spontaneous recovery this corresponds to a T1 between 1% and 15%.

Adult↗