ENLON is a short and rapid-acting cholinergic drug.
Enlon (EDROPHONIUM) is indicated for the following:
ENLON is recommended for the differential diagnosis of myasthenia gravis and as an adjunct in the evaluation of treatment requirements in this disease. It may also be used for evaluating emergency treatment in myasthenic crises. Because of its brief duration of action, it is not recommended for maintenance therapy in myasthenia gravis.
ENLON is also useful whenever a curare antagonist is needed to reverse the neuromuscular block produced by curare, tubocurarine, gallamine triethiodide or dimethyl-tubocurarine. It is not effective against decamethonium bromide and succinylcholine chloride. It may be used adjunctively in the treatment of respiratory depression caused by curare overdosage.
Published Studies Related to Enlon (Edrophonium)
Reversal of mivacurium chloride: edrophonium of spontaneous recovery in
microscopic laryngeal surgery. 
to the first twitch... CONCLUSIONS: Mivacurium, a short-acting nondepolarizing agent, is a suitable
Edrophonium requirements for reversal of deep neuromuscular block following
infusion of mivacurium. 
Mivacurium is a new non-depolarizing muscle relaxant consisting of three
stereoisomers. The two active isomers (cis-trans and trans-trans) undergo rapid
metabolism by plasma cholinesterase (t1/2 beta < 2 min)... Heterozygous patients with
atypical plasma cholinesterase levels, as well as certain individuals with normal
dibucaine numbers and plasma cholinesterase activity, are at risk for prolonged
neuromuscular block, but the block is easily reversed with edrophonium.
Comparison of the combined effects of atropine and neostigmine with atropine and
edrophonium on the occurrence of postoperative nausea and vomiting. 
To investigate the effects of different types of anticholinesterase on the
incidence of the postoperative nausea and vomiting, 100 ASA class I-II adult
premenopausal female patients undergoing elective lower abdominal surgery were
randomized into two groups... We concluded that there were no difference in
the incidence of postoperative nausea or vomiting with the use of either
neostigmine or edrophonium with atropine for antagonizing neuromuscular blockade
after the lower abdominal surgery.
Cardiovascular and autonomic nervous effects of edrophonium and atropine
combinations during neuromuscular blockade antagonism in sheep. 
OBJECTIVE: To study heart rate (HR), arterial blood pressure (BP) and autonomic
nervous (AN) effects of edrophonium-atropine combinations during neuromuscular
blockade (NMB) antagonism in sheep... Edrophonium (0.5 mg
kg(-1)) and atropine (80 microg kg(-1)) caused the mildest HR changes without ECG
and noncardiac AN disturbances, and is recommended for the antagonism of NMB in
Reversal of rocuronium with edrophonium during propofol versus sevoflurane
anesthesia... CONCLUSIONS: We conclude that the clinical duration of action after a single dose
Clinical Trials Related to Enlon (Edrophonium)
The Pathophysiology of Orthostatic Hypotension [Active, not recruiting]
The purpose of this study is to determine the cause of low blood pressure in selective
patients who have problems with their involuntary (autonomic) nervous system. These
patients frequently have had symptoms throughout their life, and their disorder might have a
genetic basis. The biochemical, physiological and pharmacological procedures in this study
should help us define the problem and perhaps lead to more effective treatment.
Measurement of Autonomic Cardiovascular Integrity in Persons With SCI [Recruiting]
People with a spinal cord injury (SCI) have limited ability to move and feel sensation below
the level of the SCI. Doctors and researchers have tests which determine the level of
function and sensation, this test was developed by the American Spinal Cord Injury
Association (ASIA) and has been modified over the years to improve use and sensitivity.
Most recently, the ASIA Injury classification Scale (AIS) was modified in 2011, but this
test does not include the evaluation of autonomic nervous system (ANS) impairment. However,
people with SCI do have impairment of the ANS and this may adversely affect how organ
systems in the body function. Specifically, ANS impairment tends to result in changes in
heart rate and blood pressure that may relate to the level of the SCI, but this is not fully
understood. In this investigation we hope to develop simple tests which will allow doctors
and scientist the ability to measure the amount of ANS impairment to the cardiovascular
system, specifically the heart. The first part of the study will be to determine the heart
rate response to several tests (administration of drugs and physical challenges) which will
change heart rate. These tests will be given to people with and without SCI and the heart
rate response will be compared between people with and without SCI. The bigger the
difference in the heart rate response to these test between people with and without SCI the
greater degree of ANS impairment in the people with SCI. Once this heart rate difference is
determined, several simple tests (deep breathing, saliva test, Valsalva) will be performed
in people with and without SCI to again compare the heart rate response. The second part of
this study will be to determine if the heart rate responses to the first set of tests
(administration of drugs and physical challenges) can predict the heart rate response to
these simple tests (deep breathing, saliva test, Valsalva). The aim of this study is to
develop a simple battery of tests which can be easily used by doctors and scientists to
determine the degree of ANS impairment to the heart in persons with SCI.
Evaluation of the Role of the Autonomic Nervous System in Sj(SqrRoot)(Delta)Gren s Syndrome [Completed]
Sj(SqrRoot)(Delta)gren s Syndrome (SS) is an autoimmune disease that affects the glands
that produce saliva and tears, causing dry eyes and dry mouth.
Researchers do not know the exact cause of SS, but they believe that it may be caused by
abnormalities in the autonomic nervous system (ANS) that stimulate these glands.
To better understand ANS function in patients with SS.
To compare information about ANS function in healthy individuals and in patients with SS.
Patients with Sj(SqrRoot)(Delta)gren s Syndrome who are 18 years of age and older, and who
are not pregnant or breastfeeding.
Participants will be asked to taper or discontinue the use of certain medications or dietary
supplements before the ANS testing.
Participants must be willing to discontinue the use of alcohol and tobacco 24 hours prior to
The study will require one inpatient admission and/or outpatient visits to the NIH Clinical
The following tests and procedures will be performed:
- Saliva, tear, and sweat production measurements to evaluate the function of glands.
- Testing of changes to the cardiovascular system, including blood pressure and blood
flow testing, and an electrocardiogram designed to evaluate hemodynamic changes
controlled by the ANS.
- Testing of changes to the gastrointestinal system, including a swallowing assessment
study, barium swallow study, and gastric emptying study designed to evaluate
gastrointestinal function controlled by the ANS.
- Tests to evaluate the ANS function in response to certain drugs (edrophonium, glucagon
- Self-reported questionnaire on ANS function and emotional/psychological well-being.
Additional procedures and tests may include the following:
- Blood samples.
- Optional skin biopsy to study sweat glands and nerve supply of the skin.
Plasma Exchange for Autoimmune Autonomic Failure [Completed]
This study will explore whether an antibody is influencing the autonomic nervous system, and
if its removal will eliminate signs and symptoms of failure in that system. The autonomic
nervous system is responsible for many automatic changes involved in everyday activities,
such as standing up, digesting food, and exercising in the heat. Antibodies fight germs but
sometimes cause health problems. Removal of the antibody is done through a procedure called
a plasma exchange.
Patients with primary chronic autonomic failure and a circulating antibody to what is called
the neuronal nicotinic receptor may be eligible for this study. To be eligible, patients
will have participated in an earlier study, protocol number 03-N-0004. Patients will undergo
tests and procedures that include an electrocardiogram, and blood collection for hepatitis,
HIV, and pregnancy. Blood will be tested for a complete blood count, clotting factors, and
chemistries. There will also be tests for liver function, kidney function, cortisol, and
thyroid. Participants will be tested for signs and symptoms of autonomic failure, and will
be asked to complete questionnaires about various symptoms before the plasma exchange, 1 or
2 weeks afterward, and then monthly or bimonthly for up to 1 year. Patients will undergo a
series of other tests. In one test, a patient is upright and blows against a resistance
(Valsalva maneuver). The quantitative sudomotor axon reflex test (QSART) uses iontophoresis,
involving application of acetylcholine, a chemical messenger, and a small amount of
electricity. QSART examines the regulation of sweating, a particular aspect of the autonomic
nervous system. There will be a test using edrophonium, given intravenously (IV), to
evaluate that drug's effects on the heart, skin, glands, gastrointestinal activity, bladder
tone, and salivation. A glucagon test, also by IV, will show patients' ability to release
the hormone adrenaline.
The plasma exchange will be performed by use of an automated cell separator. Patients' blood
will be removed continuously through a needle in the arm. Blood cells will be separated from
the plasma by a spinning process and continuously returned to circulation through a needle
in the patients' opposite arm. Blood cells that are returned will be mixed with albumin, a
sterile replacement solution. A blood thinner, citrate, will be given, to prevent clotting
of blood. This whole procedure will take about 2 hours. Patients will typically undergo five
exchange procedures in about 10 days while they are inpatients at the NIH Clinical Center.
The amount of plasma removed in a single session and the number of sessions will be set by
the NIH Blood Bank. It is expected that patients' autonomic failure will improve after
several days of starting the plasma exchange. Testing for symptoms of autonomic failure and
autonomic function testing will occur about 1 month after the plasma exchange and monthly or
bimonthly for up to 1 year. For each visit of testing, patients will be inpatients for about
2 days. If autonomic failure recurs, patients may have a second plasma exchange, with the
same follow-up tests, for about 1 year.
Page last updated: 2013-02-10