Return to Research Menu Return to Front Page

Table One

Commments On Side Effects & Safety From All CES Research Studies

 First Author,   N        Subject           Authors' Comments on Safety and Side Effects      
     Year               Description                                                           

Achte, K.A.          severe insomnia    Complications were discovered in 5 cases, 2           
1968                 patients and drug  complained of headaches, 3 felt aching in the eyes,   
                 24  abusers            1 had hysterical convulsions during the treatment.    
                                        Too strong currents caused headaches in healthy       
                                        persons. The currents were too weak to cause          
                                        convulsions and too weak to bring about               
                                        neuro-vegetative side effects.                        

England,             migraine patients  1 subject in the placebo group developed a skin       
Ronald R.        18                     irritation at the location of the electrode. She      
1976                                    suggested that sensations felt during the treatment   
                                        were responsible.                                     

Feighner, John       long term          4 of 6 long term depressed patients were dropped      
P.                   psychiatric        from the study because of massive worsening of        
1973             23  patients,          depressive symptoms.                                  
                     unresponsive to                                                          
                     medications, ECT,                                                        
                     psychotherapy                                                            

Flemenbaum, A.       anxiety,           An insignificant trend towards worsening was seen by  
1974                 depression,        the 24th week. 5 of 25 patients were not improved or  
                 28  insomnia           had become worse. The author added that side effects  
                     outpatients        are virtually nonexistent.                            
                     unresponsive to                                                          
                     medications                                                              

Forster,             inducing sleep     Although as current amplitude was increased to 20     
Sigmund          23                     volts a feeling of slight dizziness approaching a     
1963                                    headache was noted, the authors concluded that the    
                                        technic appears to be entirely safe.                  

Frankel,             insomniacs         A commonly reported innocuous side effect was mild    
Bernard          17                     blurring of vision lasting 15-30 minutes which        
1973                                    resulted from sustained mechanical pressure of the    
                                        electrodes on the eyeballs.                           

Gomez,               14 heroin          It was noted that with a higher current the patients  
Evaristo         28  patients, 7        felt uncomfortable, but there were no skin burns.     
1979                 placebo and                                                              
                     7 controls                                                               

Hearst, E.D.         psychotherapy      No patient with primary affective disorder was        
1974             28  outpatients        adversely effected by CES.                            

Hochman,             dental patients    From the results obtained during 1 year of treating   
Richard                                 a variety of patients requiring a broad scope of      
1988            600                     dental treatments, CES was found to provide a safe,   
                                        noninvasive, readily acceptable, adjunctive           
                                        analgesic modality to maintain patient comfort        
                                        through the majority of dental procedures for most    
                                        patients.                                             

Koegler, R.R.        insomnia patients  The only side effects noted were blood pressure       
1971             14                     lowers during treatment, and a slight blurring of     
                                        vision occurs due to eye electrodes, which stops      
                                        within a few minutes.                                 

Krupitsky,           alcoholic          CES was not accompanied by side effects nor           
E.M.             20  patients with      complications and was well tolerated by the           
1991                 affective          patients. CES tends to avoid side effects and         
                     disorders          complications sometimes observed in antidepressant    
                                        therapy and tranquilizers.                            

Levitt, Eugene       psychiatric        Subjects in both groups reported slight blurring of   
1975                 inpatients         vision lasting 30 - 45 minutes following treatments.  
                 13                     This supports the findings of other researchers that  
                                        the blurred vision effect is mechanically caused by   
                                        pressure of eye electrodes, and not electrical        
                                        current.                                              

McKenzie,            8 chronic          Blurring of vision due to eye electrode pressure was  
Richard              anxiety,           fairly uniform over the small control sample and was  
1971, 1976       12  depression and     not especially uncomfortable.                         
                     insomnia patients                                                        
                     and 4 controls                                                           

Magora, F.       A:  A: hospitalized    No ill-effects were noted on prolonged and repeated   
1967             20  polysubstance      observations in dogs and in humans.                   
                 B:  abusers, and                                                             
                 9   B: asthmatic                                                             
                     children                                                                 

Magora, F.           inducing sleep     No ill effects were observed after repeated           
1965             31                     experiments in the same and different individuals.    

Marshall, Alan       depressive         Although no patients were burned, the author and 1    
1974             40  inpatients         pilot subject suffered second degree burns behind 1   
                                        ear at the point of electrode contact.                

Matteson,            graduate students  4 subjects left the study due to complaints of        
Michael          62                     headaches.                                            
1986                                                                                          

Miller, E.C.         sleep induction    There appears to be no disturbing side effects;       
1965             27                     however, 1 patient did undergo a brief dissociative   
                                        episode after beginning his third treatment.          

Overcash,            anxiety            There were no reported side effects (short or long    
Stephen 1995    197  outpatients        term).                                                

Philip, P.           psychiatric        In 2 cases, benodiazepine withdrawal induced          
1991             21  depressive         epilepatientic seizures in patients devoid of         
                     inpatients         epileptic history. These seizures did not occur       
                                        during CES.                                           

Rosenthal,           psychiatric        There was no side effects reported by any of the      
Saul H.          13  patients           patients other than a transient blurring of vision    
1970                 unresponsive to    reported by several of the patients, probably         
                     meds               associated with the forced closure of the eyes by     
                                        the eyepads for 1 hour, which cleared 15-30  minutes  
                                        after treatment.                                      

Rosenthal,           outpatients with   The only side effect was the transient blurring of    
Saul H.              chronic anxiety,   vision reported by several of the patients, which     
1970             18  depression &       cleared within 15 minutes after treatment. It was     
                     insomnia           probably due to the forced closure of the eyes and    
                                        the pressure of the eye pads. It was seen less often  
                                        with later patients, and this may be due to less      
                                        tight placement of the electrodes.                    

Rosenthal,           1 psychologist,    1 subject complained of mildly unpleasant             
Saul H.              3 medical          experiences including visual disturbances lasting a   
1972             7   students,          maximum of 1 hour, tinnitus lasting several hours,    
                     1 psychiatry       hyperactivity, difficulty sleeping, and epigastric    
                     resident,          sensations. His hyperactivity and sleeping            
                     1 secretary        difficulty were gone 48 hours after the final         
                                        treatment and 1 week later he reported, "I don't      
                                        feel anxious, I feel fine." His previous mild         
                                        transient reactive depression had not occurred and    
                                        he was sleeping soundly. 2 subjects reported a        
                                        headache lasting 1 hour.                              

Sing, K.             anxiety patients   The following side effects were noted: headache,      
1967             30  with sleep         giddiness, pain in tooth, heaviness around eyes,      
                     disturbances       pain in eyes, pain behind the ears.                   

Smith, Ray B.        psychiatric        There did not seem to be any pattern of addiction to  
1993                 outpatients with   or over dependence on the CES device. There was no    
                 23  anxiety,           side effects except 1 patient who cried during        
                     depression,        treatments, and 1 was sore behind the ears when the   
                     attention deficit  electrode gel began drying out.                       
                     disorder                                                                 

Smith, Ray B.        closed head        1 patient on sham CES was seen to have a seizure. No  
1994             21  injury inpatients  negative effects from CES treatment was seen.         

Solomon,             tension headache   6 of 7 in the active group, and 7 of 55 in the        
Seymour         112  patients           placebo group had 1 or more adverse events. The       
1989                                    incidence of adverse events was not significantly     
                                        different between the active and placebo groups for   
                                        any of the reported symptoms.                         



In addition, a search was conducted of United States Food and Drug Administration records through Freedom of Information Services. The search encompassed all complaints to FDA from May, 1976 through March, 1995 (latest available data). The search revealed only 3 entries. One was an implanted stimulator (which can hardly be considered a CES device) manufactured by Medtronic Neuro Division. The device apparently malfunctioned causing the need for it to be explanted. No death or serious injury occurred. The other two were both Pain Suppressor Model 112A malfunctions. Of these, one caused the patient to suffer extreme headache pain for about 10 hours, and lack of sleep for 48 hours. The patient discontinued use of the device, took a prescription sleeping pill and then felt better. The other was a patient who was two weeks pregnant and experienced the early signs of miscarriage. This patient was instructed not to use the device while pregnant and was referred to the instruction manual which expressly states "warning": the safety of the device during pregnancy has not been established. It should be noted that the output of the Pain Suppressor is up to 4 mA which is unusually high for a CES device.

Following recommendations of the National Research Council and over 25 years of medical experience with CES in America, the FDA considers CES to be a non-significant risk modality.

Return to Research Menu Return to Front Page