Generalized Tonic Clonic (Grand Mal)


PLEASE NOTE: The following is a "textbook" definition of a tonic-clonic or grand mal seizure. Since every dog is different and every seizure can be different, we have added descriptions from various Guardian Angels so that you can get a better idea of exactly how our own dogs look and act during seizures. Those descriptions follow immediately after the source information for the formal definition. We hope this is helpful to you.

Generalized, tonic-clonic (formerly called grand mal) seizure:  The seizure begins with contraction of all skeletal muscles and loss of consciousness. The dog usually falls to his side with the legs stretched out and the head back.  This is the tonic portion of the seizure.  Sometimes he will vocalize or have facial twitching.  Vocalizations are involuntary and do not indicate pain.  Often the dog will drool excessively, urinate, defecate or eliminate his anal glands.  The tonic portion of the seizure is usually very brief and gives way to the clonic phase of the seizure.  Once the clonic phase begins the dog will have rhythmic movements.  Typically this consists of clamping the jaws and jerking or running movements of the legs. 

Following the seizure, the dog may lay motionless for a brief period.  Eventually he will get up on his feet and may appear to be perfectly normal, but typically will show signs of post ictal behavior.  These signs may include blindness, disorientation, pacing or running about the house bumping into things.  The post-ictal behavior can last anywhere from hours to days after a seizure. 

Not all generalized seizures follow this pattern.  Another type of generalized seizure is the tonic seizure, in which motor activity consists only of generalized muscle rigidity without the clonic phase.  Less common are clonic seizures where there is no tonic phase and some dogs suffer milder generalized tonic-clonic seizures in which consciousness is maintained.


Cash WC, Blauch BS:  Jaw snapping syndrome in eight dogs.  JAVMS 175:179, 1979
Parent JM Seizures, Small animal medicine 735:741, 1991
Thomas WB: Idiopathic Epilepsy in Dogs. Vet Clinics of N. Amer. Small Animal Practice 183:206, 2000


Seizure descriptions provided by Guardian Angels

Guardian Angels Nancy and Tahoe (Australian Shepherd)Guardian Angels Nancy and Tahoe (Australian Shepherd):

Grand Mal: Tahoe mostly has grand mal seizures. They occur when asleep. I have noted over the years that they have changed in duration, intensity and type. The first few seizures were always when he was asleep, and he would get rigid and start paddling his legs. Then he started to dash up from sleep, run out of the room, start circling and then go down into a seizure where he paddled, lost his bladder and twitched. Lately, he may get very rigid, shake all over, howl, twist, flip over, snap his jaws and paddle his legs. Also drools a lot. He might empty his bladder but only lost his bowels once. His eyes are very dilated and are always open. His most recent variation is he will start to stretch from front paws to back legs straight out, his head will stretch backwards with mouth stretched open, may vocalize, somehow flips to his side, mouth snapping and all over body shaking/trembling. He hasn't lost his bladder in almost 6 months. His seizures last anywhere from 30 seconds to 3 minutes of intensity, then he may slow paddle for several minutes and as he becomes conscious tries to get up but his back end is not working. I usually can get him on his feet after 30-45 minutes but he is very unsteady. Sometimes he will have temporary blindness. For information about Tahoe's partial/focal seizures, click here.

Web Angels Rita and Wolf (German Shepherd)Web Angels Rita and Wolf (German Shepherd):

Wolf's seizures are not all the same. In fact they all were unique in there own right. But usually it would start out with him looking off into space. He would get a funny look in his eyes. After a while we could see it coming. Then he would start twitching his eyes back and forth and then he would try to get up. Usually he would be asleep and wake up with one. So he would try to stand up and then he would fall down if we didn't get to him in time. Almost like he was drunk then all of a sudden it would hit him like a storm. His whole body would stiffen up and he would be hard as a rock. He's a big dog but at those times, he looked so small.

Sometimes he would fly trying to catch flies and other times his whole face would just transform. It would peel back for lack of better words and you could see all of his teeth and he just looked like a monster had taken over his body. Most times he would paddle with his legs. It wasn't the same every time but in general this is what he went through. He never lost control over his bowels but sometimes he would urinate. He definitely drooled a lot! Also Wolf would have this horrible smell that I associated with a seizure. It only happened right after or sometimes I could smell it faintly right before it happened.

Truly though the worst part was the post-ictal phase. He would pace for hours or stare into space and I would have to wonder what he was seeing. That is part of the seizure as well. His seizures would last about 30 seconds to 2 minutes long. Once in a while he would have a focal but most often they are Grand Mals.

Web Angels Mary Jane and Maggie May (Beagle)Web Angels Mary Jane and Maggie May (Beagle):

(Maggie May is a spayed chocolate/red/white Beagle. She is almost 6 years old. She had her first seizure at 3 years old)

Maggie May started out with a Grand Mal (tonic-clonic) seizure which was quite different from what she presently experiences. ALL of her seizures have happened either during sleep or just after awakening (one time). Maggie’s first seizure had a very LONG tonic (stiffening) phase. This seizure lasted 20 minutes from beginning to when she was being injected with Valium. Although quite exhausted, she came out of this seizure and had no postictal symptoms. Because of the length of this seizure, Maggie was started on Phenobarbital therapy. She had no seizures while on the medication (one and years). Since discontinuing it, Maggie had one single GM, and then started with CLUSTERS. During this past year, her seizures have all been clusters. Although these are Grand Mals, they are not the typical more violent type of seizure. You could be in the next room and not know that Maggie was having seizures!

Typical Clusters: As I have always been right next to Maggie during the initial seizure, she will come toward me or look to me and have that “glassy” look in her eyes. If she is standing or sitting upright, I will ease her down into a recumbent position. At this point she is salivating and typically loses bladder control. Maggie’s head is always bobbing at this point. Maggie will grow rigid now and be unresponsive. She has complete loss of consciousness. She proceeds to the tonic-clonic phase. After this initial seizure (3-10 minutes), Maggie will have a period where she is coherent but never attempts to get up (20 minutes - 1 hour). At this point Maggie has frequent (up to 25) tonic-clonic phases of short duration (10-20 seconds). Maggie is recumbent during this entire time (2-2 1/2 hours). Maggie vomited just prior to the tonic phase during her last two episodes.

Maggie has received Valium at the onset of each episode. I can only say what her postictal behavior is with the Valium. She has exhibited exhaustion, drowsiness, pacing (only once), increased hunger, and increased clinginess.

Maggie also exhibits muscle twitching (front legs) up to 2-3 days postictal. This could possibly be from the Valium. Maggie receives either IV or rectal Valium as well as oral Valium for 24 hours (Valium Protocol).

Web Angels Vicky and Angel Duncan (Collie) Web Angels Vicky and Angel Duncan (Collie) :

Duncan's would usually start with a staggering, then a collapse. Then back bending (bowing of the back), foaming at the mouth, kind of a snickering sound, legs paddling. No noise other than the harsh breathing, no loss of bowel or bladder control. His lips would pull up, like he was growling, but he wasn't. After this, he would lie and pant, then up and stagger around. I would usually take him outside as there were less things for him to bump into, as he didn't have good ambulatory control for probably about ten minutes or so.

During his seizures, we would always talk to him, trying to talk him through it, so to speak. Always Rescue Remedy Sundae and a snack afterwards. He was always thirsty.

Guardian Angels Debbie and Leo (Collie):

Leo, my three year old epi collie, had his first seizure at the age of 10 months and until he had other, similar episodes, I could not believe that what I was seeing was actually a seizure. They really look more like giant muscle spasms than what you ordinarily think of as seizures.

The first time, I heard a thunk and ran upstairs to see that Leo was struggling to stand and couldn't. His head banged against the window as he struggled; it looked like his back legs had fallen asleep and he couldn't get them to support his weight. His head tilted slightly - in later seizures we would see it arch back and to the side as if he had a stiff neck. During this first seizures and all subsequent episodes (generally lasting 3 or 4 minutes), he remained alert, wagged his tail when he saw us, and did not loose control over bladder or bowel. He clearly wants to be petted and held during the seizure. Sometimes he trembles or drools a bit; he licks his paws excessively both before and after. My understanding is that these are generalized seizures because more than one area of the body is involved, but they are not grand mal. His seizures occurred about once a month for about six months; when he was given a therapeutic prescription food containing BHA and Ethoxyquin, he had cluster seizures - about a dozen in eighteen hours. These seizures still looked the same. He is now on Pb and hasn't had a seizure in nearly a year!