When “Hypo” Doesn’t Look Like Hypo

When “Hypo” Doesn’t Look Like Hypo: 

Understanding Potassium Levels During Attacks

This question comes up often in the Periodic Paralysis community:

“I’ve always been diagnosed as HypoPP. My attacks are classic—loss of limbs and core, difficulty swallowing, low potassium—but today my potassium was 4.1. Has anyone else experienced this?”

The short answer is: yes—many people with Periodic Paralysis experience this, and it does not automatically mean you were misdiagnosed.

Periodic Paralysis Is a Mineral Metabolic Disorder

One of the biggest misunderstandings about Periodic Paralysis is the idea that it is defined solely by serum potassium numbers. As explained throughout my books, Periodic Paralysis is a mineral metabolic and channel disorder, not simply a “low potassium” or “high potassium” disease.

What matters most is what potassium is doing inside the cells, not just what shows up in a blood draw.

Why Potassium Can Be “Normal” During a Severe Attack

A potassium level of 4.1 is technically normal, but that does not rule out a HypoPP-type attack. Here’s why:

• Potassium can shift rapidly between the blood and the cells
• During an attack, potassium may already have moved back into the bloodstream by the time labs are drawn
• Stress, IV fluids, food, rest, timing, and even the act of being tested can alter serum levels
• Blood tests are snapshots, not real-time metabolic maps

This is why many people experience classic paralysis symptoms with normal—or even high—potassium readings.

Symptoms Matter More Than the Number

In my books, I emphasize this repeatedly:

Periodic Paralysis is diagnosed by pattern, triggers, response, and lived experience—not just lab values.

Classic features include:

• Sudden loss of limb and core strength
• Difficulty swallowing or speaking
• Respiratory involvement
• Episodes triggered by rest after activity, food, stress, illness, or sleep
• Recovery patterns that are familiar and repeatable

If the symptoms match, the condition does not magically disappear because potassium reads “normal” that day.

Mixed, Variant, and Overlapping Forms Are Common

Many people do not fit neatly into textbook categories like “Hypo” or “Hyper.” In reality, mixed and variant forms are common, especially over time.

It is also possible for:

• The same person to experience low, normal, or high potassium during different attacks
• Potassium needs and responses to change with age, illness, hormones, or cumulative damage
• Attacks to evolve while still being part of the same underlying disorder

This does not mean your diagnosis was wrong—it means the condition is more complex than the label.

A Critical Reminder About Treatment

This is why blind potassium replacement based solely on numbers can be dangerous. What helps one person—or even what helped you in the past—may not always be safe now.

Your body’s signals, patterns, and reactions matter.

You Are Not Alone

If you’ve ever thought:

• “This feels exactly like my usual attack, but the labs don’t match”
• “Something doesn’t add up”
• “Doctors seem confused by this”

You are not imagining it—and you are not alone.

Periodic Paralysis does not always follow simple rules, and your lived experience is valid medical data.

 

 

References

1. Hunter, Susan Q.
   Living With Periodic Paralysis: The Mystery Unraveled
   — Personal accounts, metabolic explanations, symptom patterns, and real-world patient experiences with Periodic Paralysis.
2. Hunter, Susan Q.
   What Is Periodic Paralysis?: A Disease Like No Other
   — Detailed discussion of Periodic Paralysis as a mineral metabolic and channel disorder, including potassium shifts and diagnostic challenges.
3. Hunter, Susan Q.
   The Periodic Paralysis Guide and Workbook: Be the Best You Can Be Naturally
   — Practical guidance on recognizing symptoms, managing triggers, understanding lab limitations, and listening to the body.
4. Hunter, Susan Q.
   A Bill of Rights for Periodic Paralysis Patients
   — Advocacy-focused reference addressing misdiagnosis, dismissal of patient experience, and the limitations of standard medical frameworks.
5. Cannon, S. C.
   “Channelopathies of Skeletal Muscle Excitability.”
   Comprehensive Physiology
   — Foundational scientific explanation of skeletal muscle channel disorders, including sodium and potassium channel dysfunction.
6. Lehmann-Horn, F., & Jurkat-Rott, K.
   “Voltage-Gated Ion Channels and Hereditary Muscle Disorders.”
   Physiological Reviews
   — Explains intracellular ion shifts and why serum potassium levels may not reflect muscle cell behavior during attacks.
7. Statland, J. M., Fontaine, B., Hanna, M. G., et al.
   “Review of the Diagnosis and Treatment of Periodic Paralysis.”
   Muscle & Nerve
   — Discusses variability of potassium levels and overlap among Periodic Paralysis subtypes.
8. Jurkat-Rott, K., & Lehmann-Horn, F.
   “Muscle Channelopathies and Critical Points in Diagnosis.”
   Acta Myologica
   — Addresses diagnostic pitfalls, including overreliance on serum potassium values.

Image: Spoon containing potassium