# Paroxysmal Exertional Dyskinesia (PED)

Paroxysmal exertional dyskinesia — PED — is another paroxysmal movement disorder. It belongs to the same family as PKD, but with one important difference: the trigger.

## What an episode looks like

PED episodes are brought on by **sustained physical exertion** — typically minutes of continuous walking, running, or other prolonged activity, rather than the brief sudden movements that trigger PKD. After enough exertion, abnormal movements begin in the muscles that have been working hardest: most often the legs, sometimes the arms, occasionally other regions.

The movements are typically **dystonic** — twisting, sustained postures — and they usually settle once the exertion stops and the person rests.

## How PED fits with PRRT2

PED's strongest genetic link is actually to a **different gene** — **SLC2A1**, which causes GLUT1 deficiency syndrome. Most cases of PED diagnosed today turn out to involve SLC2A1 rather than PRRT2.

That said, **PRRT2 is a recognized — if less common — cause of PED**. Within the PRRT2 spectrum, the kinesigenic form (PKD) is far more typical, but exertional and other non-kinesigenic forms do occur. If you are being evaluated for PED, both PRRT2 and SLC2A1 — and several other genes — are reasonable to consider on a paroxysmal movement disorder gene panel.

## How PED differs from PKD

|                               | **PKD**                            | **PED**                                  |
| ----------------------------- | ---------------------------------- | ---------------------------------------- |
| **Trigger**                   | Sudden voluntary movement, startle | Prolonged exertion (minutes of activity) |
| **Onset within trigger**      | Within seconds                     | After sustained activity                 |
| **Duration**                  | Seconds to about a minute          | Often longer; settles with rest          |
| **Most common gene**          | PRRT2                              | SLC2A1 (GLUT1)                           |
| **Response to carbamazepine** | Usually dramatic                   | Less reliably effective                  |

## Treatment

Because PED is more often a GLUT1 condition, treatment often differs from PKD. In SLC2A1-related PED, a **ketogenic diet** can be highly effective. In PRRT2-related PED, sodium-channel-blocking medications used for PKD may help, though the response is generally less striking than it is in PKD itself. Treatment is covered in [Treatments & Management](/treatments-and-management/how-treatment-works.md).

{% hint style="success" %}
**🧭 PRRT2.org Perspective**

*PRRT2.org's own perspective — our synthesis and lived experience, offered alongside the established science, not as established medical fact.*

PED is a good example of why broad genetic testing matters. Two different genes — PRRT2 and SLC2A1 — can produce a very similar movement pattern, but they call for different treatment strategies. Testing only one without the other risks the wrong answer.

In our experience, exertional patterns also blur with other PRRT2 features in ways the textbook categories do not always capture. Some carriers describe episodes that mix sudden-movement triggers with exertional ones, or shift from one to the other across life. The categories are useful, but real experience does not always sort itself neatly into them.
{% endhint %}

## Sources

The established science on this page is drawn from:

* [MedlinePlus Genetics — PRRT2 gene](https://medlineplus.gov/genetics/gene/prrt2/) — U.S. National Library of Medicine, NIH
* [GeneReviews — Familial Paroxysmal Kinesigenic Dyskinesia](https://www.ncbi.nlm.nih.gov/books/NBK1460/) — University of Washington / NCBI
* [OMIM — Entry 614386](https://omim.org/entry/614386) — Johns Hopkins University

For the complete set of authoritative references, see [Official Resources](/resources/official-resources.md).

## Continue reading

* [Paroxysmal Kinesigenic Dyskinesia (PKD)](/associated-conditions/pkd.md) — the kinesigenic form, more typical of PRRT2
* [How to Get Tested](/diagnosis-and-genetic-testing/how-to-get-tested.md) — testing for paroxysmal movement disorders
* [How Treatment Works for PRRT2](/treatments-and-management/how-treatment-works.md)


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