Tonic-clonic seizures: what happens, first aid, and why every episode should be logged

Tonic-clonic seizures, previously called grand mal seizures, are among the most recognisable and frequently misunderstood seizure types. Whether you've experienced one yourself or witnessed someone having one, understanding what happens during these seizures—and how to respond—is crucial for safety and effective management. Equally important is knowing how to document these episodes accurately, which becomes surprisingly difficult in the panic of the moment.

What happens during a tonic-clonic seizure?

A tonic-clonic seizure has distinct phases, each lasting seconds to minutes. Understanding these phases helps you recognise when a seizure is occurring and respond appropriately.

The tonic phase is the first stage. Your muscles suddenly become rigid and tense. You may cry out (not from pain, but from air being forced out of your lungs as muscles contract). Your body goes stiff, and you'll lose consciousness. This phase typically lasts 10-20 seconds, though it can feel much longer to observers.

The clonic phase follows, characterised by rhythmic jerking movements of your limbs. These jerks happen as your muscles alternately contract and relax. This is the phase most people associate with seizures. It typically lasts 30-60 seconds, though duration varies. During this phase, you may lose bladder or bowel control—a distressing but harmless symptom.

Recovery (postictal phase) comes after the jerking stops. You'll regain consciousness gradually, but confusion, drowsiness, and disorientation are common. Some people report headaches, muscle soreness, or difficulty speaking. This phase can last from minutes to hours, and memory of the seizure is often fragmented or absent entirely.

First aid: what you should do

If you witness someone having a tonic-clonic seizure, staying calm and following these steps could prevent injury:

Stay with the person. Don't try to hold them down or restrict their movements—this can cause injury and doesn't stop the seizure. Your presence is reassuring and protective.

Protect their head. Move dangerous objects away. Cushion their head with something soft if possible. Don't put anything in their mouth—contrary to old advice, this doesn't prevent tongue biting and can cause injury.

Place them in the recovery position once the jerking stops. This means tilting their head back slightly so their airway stays open and any saliva can drain from their mouth. Turn them onto their side, with one leg bent to keep them stable.

Stay until they're alert. Postictal confusion is normal and frightening. Your calm, quiet presence helps enormously. Tell them what happened in simple terms once they're more aware.

Call 999 if: The seizure lasts longer than 5 minutes, seizures happen back-to-back without full recovery between them, they've injured themselves, this is their first-ever seizure, or you're unsure whether it was a seizure.

Why logging matters—more than you might think

Here's where accurate documentation becomes vital for ongoing care. After a tonic-clonic seizure, you're confused, possibly injured, and exhausted. Your partner or carer is frightened and focused on your safety. Nobody's thinking clearly—yet these are the exact moments when crucial details slip away.

Your neurologist needs to know:

• How long the seizure lasted (people often overestimate—what feels like minutes might be 30 seconds)
• What time it happened (relevant for medication timing or activity patterns)
• What you were doing when it started (watching TV, exercising, stressed, during your period)
• Whether you remember any warning signs (aura)
• How long recovery took and what you experienced during postictal state
• Any injuries sustained

With pen and paper, by the time you're alert enough to write, days may have passed. Details blur together. If multiple seizures happen, distinguishing one from another becomes impossible. You end up telling your neurologist "I had a few seizures last week" with few specifics—and your doctor has less information to adjust your medication or identify triggers.

Digital logging: capturing what pen and paper can't

A digital seizure tracker lets you or a carer log the seizure the moment it's safe to do so. Record the exact time, duration, what triggered it, and postictal symptoms. If you can't log it yourself while confused or exhausted, you can invite a trusted family member or carer with write access to your log. They can document what they witnessed whilst you recover.

Over time, patterns emerge that you'd never spot manually. The app's stats dashboard shows whether seizures cluster at particular times of day, specific days of the week, or after certain activities. Your neurologist sees not just individual episodes but genuine trends—which is far more useful for adjusting treatment.

After tonic-clonic seizures: what to expect

Recovery varies considerably. Some people bounce back within an hour. Others experience postictal state for a full day—confusion, severe fatigue, mood changes, or memory problems. Logging these after-effects helps you understand your personal seizure pattern and recover safely.

Never drive until you're fully alert, and avoid hazardous activities for several hours. Your body's been through genuine physical trauma, even though you were unconscious for it. Rest is essential.

Whether you've had one tonic-clonic seizure or experience them regularly, documenting each one accurately gives your healthcare team the clearest picture of what's happening. That clarity leads to better treatment decisions and, ultimately, better seizure control.