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Seizures After Anesthesia

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I am a board-certified anesthesiologist in Lake Tahoe, California. I write from the perspective of both a doctor and a patient.

Imaging studies and EEGs are used to define and diagnose post-op siezures.

Imaging studies and EEGs are used to define and diagnose post-op siezures.

Seizure as a Complication of Anesthesia

Seizures after anesthesia are rare but nonetheless recognized as a potential complication.

Anesthetic medications act on the central nervous system, so it is not surprising that various medicines influence the seizure threshold. Some of the medications used during anesthesia lower the threshold, making them more likely. Others raise the threshold, making fits afterward less likely. Further, there can be direct toxic effects of some medications, such as local anesthetics, that cause seizures when absorbed in large amounts into the bloodstream.

Who Is at Risk?

When seizures do occur in the postoperative period, they happen most often to those who already have epilepsy or other related disorders.

They are most common in people whose seizures are not well controlled before surgery and in patients who are undergoing brain surgery.

Seizures after surgery and anesthesia can rarely occur as random events. An occurrence in a postoperative patient who doesn’t already have a disorder should prompt a search for structural or chemical brain abnormalities.

Prevention in Epileptics

If you have epilepsy and your surgery is elective, you should work closely with your neurologist to optimize your anti-epilepsy drugs prior to surgery. Good control with stable doses of medication will decrease the risk of seizures after surgery.

It will also be important to have a meeting ahead of time with an anesthesiologist or nurse working in a pre-op clinic. Make sure they know about your epilepsy and current medications. The standard pre-op instructions may say not to take any medication, but you should specifically ask about seizure medications, especially if you are prone to them if you miss a dose of medicine.

Also, if you have motion sickness or known issues with nausea and vomiting after anesthesia or with pain medications, ask for a prescription for an anti-nausea medicine with your pain meds. If you can’t keep your drugs down, you are more likely to have an episode in the first few days after surgery.

Pre-Existing Risk Factors

  • Pre-existing epilepsy or seizure disorder, especially if poorly controlled
  • Lengthy surgery or surgery that lasts longer than the effectiveness of the last dose of medication in epileptics
  • Pre-existing brain abnormalities such as a tumor, aneurysm, or scarring
  • Alcoholism and alcohol withdrawal
  • Illicit drug use
  • Local anesthesia in large doses
  • Certain anesthetics in combination with any of the above

Causes in Non-Epileptics

When a seizure occurs after surgery in someone who hasn’t had a previous history, several reasons would initially be suspected.

  • Alcohol withdrawal may be the most common reason.
  • Chemical or electrolyte abnormalities can be a rare cause.
  • A previously unknown or undiagnosed brain tumor or other problem may exist.
  • Seizure is a known complication of an overdose of local anesthetics like lidocaine.

Further workup will depend on the suspected reason.

If alcohol withdrawal is suspected, the patient will usually be admitted to the ICU and medications ordered to counteract the dangerous effects of withdrawal.

The involvement of a neurologist is recommended in cases where the cause is not obvious.

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Read More From Healthproadvice

There is some debate about the ability of the major anesthetic drugs to influence seizure activity. This is further complicated by the fact that each drug may have different effects at different doses.

Anesthesia Meds That Probably Make Seizure More LikelyAnesthesia Meds That Probably Make Seizure Less LikelyUndetermined or Varies by Situation





Other Benzodiazepines


Local Anesthetics


Other Inhaled Agents




From the Operating Room...

Of note, in my residency, I had a young man (with no history of seizures) experience a grand mal seizure as he woke from general anesthesia for testicular tumor excision. Blood work did not show any abnormality, but since his testicular biopsy was positive for cancer, we ordered a CT scan of the brain. He was found to have a lesion on his brain, probably unrelated to his cancer, that was almost certainly the seizure focus. He had a past history of methamphetamine drug abuse, but his drug screen after surgery was negative for stimulants. He did on further questioning report previous trauma to the head which could have accounted for the lesion seen on imaging. We published this experience as a case report in a leading anesthesia journal since the anesthesia gas we used was still fairly new and had unknown potential to lower the seizure threshold.

- Hilty, CA and Drummond, JC; Seizure-like Activity on Emergence from Sevoflurane Anesthesia; Anesthesiology: Nov 2000; 93(5); 1357-9.

The Bottom Line

  • Seizures after surgery are sufficiently rare that you should only really consider them a possibility if you have a pre-existing condition that puts you at higher risk.
  • If you drink alcohol in excessive amounts or have had signs and symptoms of withdrawal in the past, make sure the anesthesiologist and surgeon are aware of this.
  • If you are an epileptic, make sure your neurologist is aware that you have scheduled surgery. Ask if you need a blood test to check the levels of your medicine. Find out when you should take your medication before and after surgery and discuss this with the anesthesiologist before undergoing surgery.
  • If you use drugs, be honest. We can deal with many situations, but if we have to play a guessing game, we are less likely to be successful.
  • Discuss all medication and other medical conditions with the anesthesiologist, especially if you take medication that is known to affect your blood chemistry and electrolytes (diuretics, for example).

This content is for informational purposes only and does not substitute for formal and individualized diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed medical professional. Do not stop or alter your current course of treatment. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.


gaynor on May 11, 2019:

Hello there, my mum went into hospital after a fall, she was diagnosed with a hip fracture and a bleed on the brain. She was sent to the fracture unit and they informed me that they would not operate on the hip until the brain had settled. The following day she had a hip operation and a few hours later she had massive seuizers that conitinued for several days. This resulted in my mum not being able to function again. Do you think this was down to the operation ?

Safdar on October 13, 2017:

My daughter had a minor surgery when she was 5 months old for her hips dysplasia, and she was given general anesthesia twice on different occasions before the surgery. She was then put on a cast for three months and towards the end of the third month, we started noticing some odd behavior in her. Her eyes began to move from one side to another and sometime up and down. She stopped grabbing things, and showed almost no interest in focusing at things as well. Almost no eye contact with people or other objects. We got worried and reached out for some expert's advice.

After so many back and forth visits to different doctors including neurologists, it was found out through an EEG test that she was having continuous subclincal seizures and they were a lot in number. Doctors put her on anti-seizure medicines(Onfii and Kepra) to stop the seizures, but it did not really help. They then increased the dose which did help a little bit in slowing down the frequency of her seizures.

Also, they have pretty much done every possible tests including MRI(she was given anesthesia for the third time) on her to find out the reason behind the seizure, but every test result has come negative

On the other side, we(family) went through all videos of her which had been recorded before her surgery, and we were shocked to see her behavior being perfectly normal. She was paying attention to almost everything, making perfect eye contact with people, much more active etc. But now she is a way behind her age, her head control is extremely poor, very low body tune, does not eat a lot, cant sit without a support etc.

Therefore, we highly suspect that the general anesthesia, which was given to her, has triggered the seizures. At this point, we are feeling very helpless and have no idea what can we possibly do to make our become normal again.

If you have any comments or suggestions, they would be greatly appreciated.


Patricia on September 30, 2017:

I don't agree that these seizures occur mostly in patients that already have preexisting seizure history. My Aunt just recently had kidney surgery and she has NO history of seizures but had her first seizure within 24 hrs after the surgery . The Drs. are trying to determine the cause of

the seizures since they are continual. I feel they already know the cause after reading the comments OTHERS HAVE MADE which is the anesthesia. But why are they not willing to admit it is the bigger question.

Daniela on July 20, 2017:

Hi, my cat had an abdominal surgery due to Small bowell obstruction (due to a hair ball) 2 days ago. He was discharged today from the hospital and now he had a seizure. It's the first time that something like this happen to him and he is 9 yo. He is taking reglan and had a heavy plan during hospitalization. What may be the cause of this episode? Thank you

Carolyn Smith on February 18, 2017:

I had knee surgery last Friday, a week ago. Everything went great till the falling Tuesday morning I started having peti mal seizures that woke me up at 1 in the morning I got up told my husband then at around 9am I had a grand mal seizure got a doc appt. had another in his office then was taken by ambulance to the ER. I've had epilepsy since I was 12, but haven't had a seizure in 20 yrs. Had surgery before on my other knee & this never happened. Was taking the pain pill Norco I was given for pain after the surgery, but stopped it the day before this happened. They checked my levels at the ER & my Dilantin was 4 should be between 10-20. How could it have gotten so low? I haven't missed any.

Jimmy g on May 10, 2016:

I had no problems with health issues till later. When I was a kid I caught no childhood sicknesses. (Measels,chickenpox etc....even when put beside another child) Then I got in my mid- thirties and everything started happening. Spinal menegitious was first,then I had a stent for a blood clot then a triple by pass for three clots at my heart. (I was 39). Afterwards about 3 or 4 months,I started having seizures at night. As the weeks and months went by they got worst. They raised the doses of the medication to where it is to this date.(700mg of Lamotrigine/ generic of Lamictal) I am 52 now and had a heart attack in January, went to the hospital and had another stent put in. While I was there they said I had a seizure and they said anxiety brought it on. (You don't say) They added keptra 500mg morning and 250mg night. After the keptra ran out that was it (so I thought). My wife has said I have small ones once in a while. I do fill like I'm out of place or in a dream state when getting ready to have one. I also feel weak and start not to be able to move my hands even if I try.........then thats it I'm gone!

Sherri R on December 30, 2015:

I had surgery in Sept to remove an ovarian tumor. In the past, i had experienced post surgery migraines with nausea, so this time I was given a patch to wear. I was told I could wear this patch for a few days and did so until it made my vision blurry. A few days later I ran a 4 miler race, I was exhausted and probably shouldnt have. I then had a grand mal seizure in my sleep on Oct 3 and was nonresponsive for 30 min after. I was taken to the ER where all tests showed no concerns. I followed up with a nuerologists who did and EEg and wants to put me on seizure meds. Because he said my brain showed signs of aggitation in drowsy state.

After reading the side effects, I declined meds. I feel this seizure was a one time occurance stemming from the surgery and doing too much after surgery. I feel like I am a healthy individual. My husband however is bery concerned. Because he witnessed this seizure it scared him very much. My mom died at age 60 froma stroke. So that is my fear.

My question is, do you think I should worry about a reoccurance?

Lip9000 on June 07, 2015:

Tony Higgens can you please email me I wanted to speak to you on the phone about what your wife went through as my girlfriends grandmother is experiencing the exact same thing

farah on February 26, 2015:

My mother suffered an ishemic stroke 3 years ago. She went in for an elective laporscopy to remove her gall bladder a month ago. After surgery she suffered a seizure for the first time. The docyors have put her on epival 1500mg. My question is could the seizure be a one off event caused by the stress of surgery?

Eve on January 05, 2015:

Sue, I am so very sad to read this about your nephew, I am so sorry, prayers for you and family.

Is there a way to send Tahoe Doc a more private message as I would like to tell what recently happened with my daughter in regards to anesthesia ans several severe seizures afterwards that almost killed her? I would really like privacy to talk about this with Tahoe Doc rather than for the whole world to see. I am extremely worried and concerned for my child. She is 27 yrs old. I am so very afraid for her now.

Sue on October 08, 2014:

My nephew had surgery last week. He was supposed to go home Friday. Late Thursday night he had a seizure, fell down, hit his head and died. He was only 34. He had no history of seizures. No one in the family does. It is surreal.

Tris on October 08, 2014:

Hi there,

I am currently preparing for a presentation looking at the fitting patient. I have been asked to look at the risk and risk management with in anaesthetics and PACU. The article i have read has been very helpful but wondering if you had any ideas which i could further research to aid me.

Many thanks

TahoeDoc (author) from Lake Tahoe, California on June 18, 2014:

Thank you Tony, for your contribution. I'm sorry to hear that this happened to your wife. I've not seen this and it would be indeed rare- making it all the more frightening and frustrating for you and her.

There are medicines that can cause abnormal movements, but it would be hard to say what is most likely. Other meds to consider include some of those, like metoclopromide, that are given for nausea. But, as you have probably been told by now, this is usually only with long-term use and not one time or occasional administration.

Again, my best wishes for you both and thanks for sharing your story.

Tony Higgins on June 17, 2014:

My wife recently had day surgery to remove one ovary and had severe jerking movements in the recovery room minutes after coming round from the surgery. This led to her been admitted to the HDU for 1 week. The jerks were so extreme that the mattress was placed on the floor of the HDU for 2 days. She was initially giving Diazapam and then Clonazepam to try to counteract the jerks. The episodes reduced in severity but not in number after this. They were usually every 20 minutes and lasted 30 - 45 seconds with some lasting 2 minutes. After 2 days this reduced to every 30 minutes with the same duration 30-45 seconds. Her heart rate would jump to 140BPM for the duration of the episode dropping back to 65 BPM when the episode subsided.

One of the anesthetists thought it may have been related to the anesthetic Propofol. He contacted a neurologist in another hospital and it was arranged for here to go see the neurologist after being discharged from the maternity hospital where the day surgery was performed.

She continued to have these jerking movements in both legs and her right arm but always remained conscious and alert throughout. It was very frightening for her and indeed myself witnessing them as she would thrash about very violently in the first 2 days. When the clonazepam kicked in the episodes reduced to tremors again always her 2 legs and right arm never her left arm.

The neurologists noticed from her surgery notes that she was administered Pethadine in recovery and he felt that it was this that was the more likely cause of the myoclonus jerks and not the Propofol.

The tremors continued and she contacted the neurologists office were she got an appointment to have an EEG which was only carried out yesterday. She got a call to say that the EEG result was normal. She is still getting the jerks although they are mild she is very worried and has lost a lot of confidence, she has not driven her car since even though she was cleared to do so by the neurologist.

It seems to be a very little understood condition as it is obviously a rare occurrence but I wish we knew if it was something she is going to have to live with or can it be treated with a happy outcome.

The surgery to remove painful ovary was a complete success with the pain totally gone. It turned out there were adhesions after a tube removal a number of years back. Its funny that up to the day of the surgery she was in a lot of pain and couldn't wait to have the ovary removed now she wishes she had left well enough alone.

I am hoping that with time she will be rid of the myoclonic jerks and also be free of the ovarian pain that had plagued her for 18 months.

The next step will most likely be a brain scan to see if there was anything that left here predisposed to having these jerks after surgery. The funny thing is she has had a number of gynecological surgeries over the last ten years and never experienced anything like this.

TahoeDoc (author) from Lake Tahoe, California on March 27, 2014:

Hi Tracirn- thanks for visiting...

I see your confusion here and I don't know the answer for sure. Her pre and postop glucose measurements were both adequate. She had an interscalene block, so local anesthetic toxicity is definitely the first thing you try to treat. It would be less likely for this to manifest 2 hours later, but not unheard of, especially if she received local anesthetic in the wound at the end of surgery also, a common practice. The fact that intralipids had no effect argues against that, however. The fact that benzodiazepines were also ineffective makes me wonder if she could have been having a reaction other than seizure (such as severe myoclonus from a drug like propofol or etomidate) although this is unlikely with experienced providers as witnesses.

Potentially, other unrecognized issues could cause seizure, especially after anesthesia... head bleed is always possible-was there significant intraop/postop hypertension?, Or could she have other intracranial pathology like an undiagnosed tumor that served as a seizure focus such as what happened to my patient in my anecdote above, and make the seizure more resistant to usual therapies). Alcohol withdrawal is also possible and I've seen that a few times, but really only in patients who were ill and either unable to drink or in the hospital for 2-3 days prior without access to etoh...

That's quite an interesting question and I hope you are eventually able to find out some follow up on that. If you do or if you have other questions, please let me know.

Tracirn on March 27, 2014:

I had a patient today that seized in PACU in our surgery center. She had an interscalene block pre-op, her surgery was 2 hrs long. She was a diabetic, sugar pre-op was 104... post-op 142, and 146. VSS. Intra-lipids were given without results, as well as a total of 6 mg of midazolam in PACU. Seizing continued. She was transported to the nearest ER. Any ideas?

TahoeDoc (author) from Lake Tahoe, California on August 20, 2013:

Hi Kim d,

That is odd, indeed. A couple possibilities--- Did you have an EEG to verify that there was truly seizure activity in the brain?

If yes, then it is very puzzling. I'm not too sure what they would have done differently for the foot surgery. One thing would be if they use a lot more local anesthesia and you are very sensitive to it. Local anesthetics can cause seizures, but it usually takes quite an overdose OR injection into a blood vessel (in which case I wouldn't expect the seizure to happen in the recovery room, but the operating room unless they are injecting local at the end). Another thing that is different is the use of a tourniquet to keep blood out of the surgical site in foot surgery. When the tourniquet is released at the end, the blood chemistry changes a little bit. I can't think of why this would cause seizures unless you are very sensitive to something that changes.

The other possibility (and maybe more likely) is that these are pseudoseizures or something else. If there was no seizure activity on EEG (and I suspect they weren't able to get one on the spot because that's very difficult), there are a couple of options. One is that you have a severe form of shaking related to anesthesia. Shaking/Shivering is a common side effect but some people have is so bad that it looks like seizures. Some people's muscles actually have a hard time relaxing because they are shaking so hard.

The other possibility is that this is 'myoclonus'. This is another form of involuntary muscle movement from some anesthetic drugs. I've seen it most often when people are going to sleep and it can and sometimes does look like seizure activity with the way the extremities move. I've almost been fooled before. Again, myoclonus usually happens when the drug is given but I can think of a few times when I've seen this as a more delayed reaction (after a 'drip' of etomidate or propofol for example).

If it's one of those 2 things or something related, it may have happened after the foot surgeries because you are under anesthesia longer for those than you would be for an appy (I'm making the assumption that you had general anesthesia for each of them and that the foot surgeries were longer than the apply).

If you remember the events, then it is NOT seizure activity- that's another clue. Of course, not remembering it doesn't necessarily mean anything since you were recovering from anesthesia.

But, anesthesia can provoke seizures in someone who is predisposed. If you haven't already, you need a referral to a neurologist to help you figure this out. They may or may not decide you should have an EEG to help sort this out.

Good luck and thanks for the interesting question.

Kim d on August 19, 2013:

I have had three foot surgeries and two of them I had seizures in the recovery room on and off for about an hour. It's has let the doctors very confused. I had my apprndix out last year but I had no seizure problems in recovery. Just two of my foot surgeries. I wonder if it has to do with the. Giving me something different for the two foot surgeries compared to the abdominal surgery. I don't believe I have epilepsy because my seizure only occur after anesthesia

TahoeDoc (author) from Lake Tahoe, California on July 02, 2012:

Hi Jacki. Grand mal seizures usually are not a complication that far out from the anesthesia. Sometimes, the stress of the illness, the surgery and the anesthesia can uncover a tendency to seizures that were never seen before.

You need to be seen by a neurologist, if you haven't been already (if the seizure happened in the hospital, you probably were- or at least had an EEG). Follow up closely so that they can get to the bottom of the reason you are having seizures, if they have continued. Make sure you know what tests they are doing and what they expect to find out from each one so that you get the best explanation that you can.

Good luck- sounds like you have been through a lot recently and I hope things get better soon.

Jacki on July 02, 2012:

I had an er surgery to have part of my colon and sm intestine removed. I had a few complications from the surgery that lead to a 15 day stay. within a week I started having grand mal seizures. Could this be another complication?


Didge from Southern England on June 08, 2012:

Amazing hub TahoeDoc! Nice post.

Mmargie1966 from Gainesville, GA on April 18, 2012:

Great Hub, Doc! The alcoholism related issue is quite a surprise (I was married to a recovering alcoholic who went through several surgeries, but didn't have any seizures).

I voted up and interesting!

Thank you for sharing, and glad to have you on my team.


alliemacb from Scotland on April 04, 2012:

This is an interesting hub that sets out potential risks clearly. Voted up!

Pamela Oglesby from Sunny Florida on April 03, 2012:

This is very important information to know if you are scheduled for surgery. I know it is important to let the anesthesiologist everything about your past history for the best outcome. Great information.

TahoeDoc (author) from Lake Tahoe, California on April 02, 2012:

Well, thank you Marcy! My goal in writing has always been to bridge the gap between health care givers and recipients. I can't imagine how confusing it is sometimes to people who don't have the 'insider' knowledge.

Marcy Goodfleisch from Planet Earth on April 01, 2012:

What incredibly helpful information for those of us who might have surgery someday (and that's just about everyone). As with many, I've been curious about the drawback and dangers of various anesthesia methods, but I've not really known where to look for information. You have summarized some basic details for us in an understandable and usable way. Thanks! Voted up, useful and interesting!

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