In a recent chat with Glamour, actress Brooke Shields shared that something scary happened to her in New York last September. She said, "I was getting ready for a show and drinking a lot of water, not realizing I didn't have enough salt. I was waiting for an Uber. When I got to the bottom of the stairs, I started to look strange, and the people I was with asked, 'Are you okay?'"

The 58-year-old celebrity recalls a time when she went into a restaurant feeling out of it and then had a scary moment of "foaming at the mouth, turning blue, and struggling to swallow her tongue." She openly shared that she "overhydrated" herself by drinking too much water.

Dr. Jonathan Parker, a neurosurgeon at Mayo Clinic in Arizona, explains that drinking too much water can actually trigger some seizures.

"A tonic-clonic seizure is a kind of seizure where your muscles get all stiff and then start jerking," he said. Parker clarified that during this type of seizure, weird electrical signals in your brain mess things up and make your body do strange things.

Tonic-clonic seizures can happen for different reasons. "Unprovoked ones are caused by things like structural problems such as tumors or a history of previous strokes, things you can't easily identify," Parker explained.

On the flip side, provoked tonic-clonic seizures can happen due to certain medications, head injuries, high fever, or problems with your body's electrolytes. What Brooke Shields experienced likely falls into this category of possible causes.

Parker explained that regular drinking water, which is naturally occurring, doesn't have many electrolytes. So, if you drink too much of it, it can lower the level of electrolytes in your blood and mess with your sodium levels, leading to a seizure. "Your blood sodium level can drop significantly when you drink too much water because the water doesn't have as many electrolytes as your body does, and it dilutes what's in your blood," he said.

How to know if you're consuming an excess of water.

How do we know when we've had too much water, and how can we avoid overwhelming our bodies?

Dr. Parker points out that several factors play a role here, like your body size, how long you've been out in the heat, and if you're sweating a lot. He emphasizes that it's pretty rare for people to drink so much water that they mess up their electrolyte balance enough to have a seizure.

The Mayo Clinic suggests that in regular weather, the average amount of fluid you should have is about 15.5 cups for men and 11.5 cups for women. This includes all sorts of fluids, not just water, including other drinks and foods that help keep you hydrated.

Parker recommends a simple approach to figure out how much water you need: listen to your body's thirst signals.

"There's no fixed rule for the right amount of water because it varies for everyone, but you should drink when you're feeling thirsty," he explained. "For instance, if you're drinking more than a liter of water every hour, and you're indoors without sweating or feeling thirsty, you might be overdoing it."

You can also check the color of your urine. If it's pale yellow or nearly clear, that's a good sign that you're well-hydrated. If it's darker, it's a hint that you should probably drink some more water.

How to recognize the signs of a tonic-clonic seizure.

When Shields shared her experience, she mentioned that the folks with her noticed her acting strangely, which Parker related to a sort of "warning signal" some people get right before a seizure.

Imagine it as a little alert, like a strange sensation in your chest or a tingling in one part of your body, or even a sense of déjà vu. These are some of the early signals that can pop up right before a seizure occurs, according to Parker.

When it comes to treating tonic-clonic seizures, the most effective way to prevent another one is to get rid of whatever caused it in the first place. Whether it was too much water or a specific medication, if you avoid the trigger, you can likely prevent another seizure from happening.

Unprovoked seizures are a bit more complicated because they don't have a clear cause. In such cases, doctors might recommend taking epilepsy medication or even consider surgery.

Dr. Parker explained, "If it's provoked and you remove the cause, it's unlikely you'll have another seizure because you won't encounter that cause again. But if it's unprovoked, there's a risk it could happen again."

In any case, if you ever experience the sensations we've talked about, be sure to reach out to a healthcare professional right away.