Writing Archive

Hot Baths and MS: When Diagnosis Meant Getting Into a Tub

Before MRIs. Before lumbar punctures. Before McDonald criteria. If doctors suspected you had multiple sclerosis in the mid-20th century, they had a diagnostic tool: they'd put you in a hot bath and see if you glitched out.

I'm not kidding.

The Hot Bath Test (1950-1983)

In 1950, the hot bath test was developed as a diagnostic tool for MS and was used until the early 1980s, when MRI and cerebrospinal fluid analysis replaced it. The concept was straightforward: if lying in a bath of warm water caused or worsened your neurological symptoms, it was taken as evidence that you had multiple sclerosis.

The test capitalized on what's now called Uhthoff's Phenomenon: the temporary worsening of MS symptoms when body temperature rises. Between 60% and 80% of people with MS experience heat sensitivity, and over 80% of MS patients develop neurological signs during hyperthermia, with 60% of those being "new" symptoms the patient hadn't experienced before.

So yeah. Getting into hot water could make you lose vision, develop weakness, experience numbness, or reveal symptoms you didn't even know you had. Wild diagnostic strategy. But also a giant disruptor of normal life for many of us.

Wilhelm Uhthoff and the 1890 Observation

In 1890, German ophthalmologist Wilhelm Uhthoff first described exercise-induced amblyopia (vision problems) in multiple sclerosis patients. He observed 4 out of 100 MS patients who developed reversible vision symptoms from increased body temperature, describing it as "marked deterioration of visual acuity during physical exercise and exhausting."

Here's the thing: when Uhthoff studied this phenomenon, he thought exercise was the cause and he missed that it was actually the elevation in body temperature doing the damage. It took six decades for someone to connect the dots and turn heat exposure into a diagnostic tool.

The phenomenon wasn't named after him until 1961, when another researcher gave it the eponym "Uhthoff's Phenomenon."

Why Hot Baths Reveal MS

The mechanism is fascinating. Demyelinated nerves (the hallmark of MS) are extremely sensitive to temperature changes. When you heat up the body, partially demyelinated axons basically stop conducting nerve signals properly. The symptoms are always temporary, lasting less than 24 hours, and resolve once the body returns to normal temperature.

This is why MS patients throughout history complained about: symptoms worsening in summer; problems after hot showers or baths; issues during fever or infection; difficulties in hot climates; and trouble after exercise.

They weren't imagining it. Their nervous systems were literally temperature-dependent.

Why We Stopped Using Hot Baths for Diagnosis

A 1983 study found that the hot bath test was abnormal in only 35% of patients with definite MS, and rarely added diagnostic information when other tests were available. Plus, you know, it had "potential complications," which is a polite way of saying "making sick people get into hot water to make them sicker is maybe not ideal."

By 1980, MRI technology advanced enough to visualize demyelinating lesions directly. Why make someone temporarily worse when you can just... look at their brain and spinal cord?

The Irony

The hot bath test represents a weird moment in medical history where we used the disease's own mechanism against itself for diagnosis. We made people experience pseudo-relapses to confirm they had the thing causing the pseudo-relapses.

And here's the kicker: until 1983, clinicians were recommending that MS patients stay home if outside temperature exceeded 30°C (86°F), avoid tanning, use sunglasses, and limit physical exertion. The phenomenon Uhthoff described in 1890 dictated MS rehabilitation strategy for over 100 years, limiting the use of thermal treatments and restricting aerobic exercise.

We've since figured out that controlled exercise and physical therapy are actually beneficial for MS patients, but for decades, heat sensitivity shaped the entire approach to MS management.

What This Tells Us About Diagnosis

The hot bath test is a perfect example of how diagnostic tools evolve. In 1950, it was state-of-the-art. By 1983, it was obsolete. Today, it's a historical curiosity; though the phenomenon itself remains extremely relevant for MS patients managing daily life.

It also highlights something important: sometimes the body tells you exactly what's wrong, if you're paying attention. Heat sensitivity isn't a vague complaint. It's a specific, reproducible, physiological response to demyelination.

The question is whether anyone's listening.

PS: Personal anecdata: I survived living in Phoenix, Arizona and went from being a desert-rat kid that played outside in the heat, endless soccer games in 110°F+ temps, to being absolutely wilted from age 14+. The difference in pictures of me as a prepubescent and thus presymptomatic kid and a suddenly indoorsy kid are stark.

Sources

• Panginikkod S, et al. (2022). Uhthoff Phenomenon. StatPearls.
• Opara JA, et al. (2016). Uhthoff's phenomenon 125 years later: what do we know today? J Med Life.
• Rolak LA, Ashizawa T. (1983). The hot bath test. JAMA.

Book Recommendation

T. Jock Murray's Multiple Sclerosis: The History of a Disease (Demos Medical Publishing, 2005) is an excellent, accessible history of MS from medieval case reports through modern treatment. Murray covers the hot bath test, Uhthoff's work, and the evolution of diagnostic criteria in fascinating detail.

Personal Case Post: What Compliance Actually Looked Like

This week I wrote about how clinical "compliance" assumes privileges most patients don't have. As someone that has spent a distressingly large number of years in online patient advocacy spaces, I've sometimes been asked: was I non-compliant with medications before I found ones that worked?

No. I was extremely compliant. That's the problem.

The Cronenbergesque Joy of Reviewing Historical Data

I took SSRIs for years. Prozac, Zoloft, Lexapro, others I've forgotten. Exactly as prescribed. Full trial periods: six weeks, eight weeks, twelve weeks. They did nothing for my anxiety, or made it worse, or made me feel nothing at all, which is different from feeling calm.

Benzodiazepines made me foggy and disconnected but not less anxious. The anxiety was still there, but just... harder to articulate. Like being trapped behind frosted glass. Just watching yourself not get better.

When I read my old medical notes now, there's this weird body horror to it. Not the obvious kind; not the MS lesions or the chemotherapy destroying my immune system. The subtle kind. Watching past-me compliance-perform my way through treatments that were chemically incapable of working for my neurology. Watching the clinical narrative frame that failure as mine.

Basically: "Patient remains anxious despite multiple medication trials."

And never: these medications aren't designed for autistic neurology.

Just: patient remains broken.

The only antidepressant that ever helped was Wellbutrin, and it didn't work the way it was supposed to. It made my anxiety coherent instead of treating it. Feral panic became focused existential dread. I could think through it instead of just surviving it. It civilized my autistic anxiety enough that I could function through MS fatigue by running on terror with a purpose.

The other medication that actually worked was cyproheptadine, prescribed in 2013 by a psychiatrist who'd treated trauma clients at the VA. Turns out my childhood was like fucking Nam, and the clinicians who understood combat trauma were better equipped than standard psychiatric approaches.

Sadly, I can't take it anymore (cognitive side effects after the September brain damage are really pronounced) but it worked when nothing else did.

My pattern: medications that worked were prescribed by clinicians who understood complex presentations. Not standard approaches.

Now I'm on Buspar and Guanfacine thanks to having a neurologist who is also a psychiatrist.

The Technical Part

SSRIs broadly increase serotonin across your whole system. For autistic neurology already dealing with sensory overwhelm and emotional dysregulation, flooding the system destabilizes everything. It's like turning up all the volume knobs at once when some channels are already too loud and others are too quiet.

Benzodiazepines force GABA calm; they sedate your nervous system. For autistic hyperarousal, it's throwing a blanket over a fire alarm. The alarm is still going off, you just can't respond anymore. (This is not fun. I could never understand recreational use of these drugs.)

Buspar gently modulates specific serotonin receptors instead of flooding the whole system. Guanfacine targets the norepinephrine system: the actual fight-or-flight response driving autistic hyperarousal.

So, basically: for the first time in my life, I'm sleeping peacefully.

The Bigger Picture

My compliance was never the problem. I took every medication exactly as prescribed. The treatment approach was wrong from the start.

The compliance framework assumes the prescribed treatment is appropriate. If it doesn't work, the failure must be patient-side. Treatment-resistant. Difficult. Fundamentally broken.

But treatment resistance isn't always about the patient. Sometimes it's about prescribing neurotypical treatments for neurodivergent conditions.

This flaw in the framework extends beyond psychiatry: I'm now on Rituximab for my MS as of November 10th 2025. It was delivered to my hospital chair with a big ole CHEMOTHERAPY bag tag. Targeted immune system demolition. It's working, I guess. But it changes nothing. Existence continues as it oscillates between casual body horror and really fucking cinematic body horror. The combination of chemotherapy working AND anxiety medication that works with my neurology means I can actually rest while my immune system gets strategically destroyed and rebuilt.

I spent decades being compliant with treatments that couldn't work for my specific physiology. The medical narrative framed it as my failure.

This is why I felt so triumphant in the ER in September when the med school kiddos were saying words I knew meant "lmao lol yea some kind of MS" and fawned over me being something "uncommon" from their textbook rather than "just another fat, poor, middle-aged white woman having a panic attack."

As med students watched in respectful awe while my Uhthoff's-roasted eyes quivered in their sockets with pendular nystagmus, it was almost transcendent for me. I was being validated.

The compliance framework assumes your neurology matches the neurology the treatments were designed for. When it doesn't, you can be perfectly compliant and still fail to improve. The system will still frame that as your problem.

If twenty years ago someone had said "SSRIs aren't working, let's try something that targets norepinephrine dysregulation instead," I would have slept peacefully twenty years earlier.

I was compliant every time I had health insurance good enough to seek care.

But the medications were wrong. The framework blamed me.

That's not an edge case. That's a fundamental design flaw.

And I will treasure every moment of improved life I have while surviving this dynamic.

Livejournal-ass Post About Psychosocial Intake Questionnaires

The Intake Interview Problem

This week I wanted to publish the prologue of my memoir project but I've been busier than planned, between both myself and my beloved partner/fiancé being sick and just... life.

I'm setting up with a new provider network. This means intake interviews. Every new clinician needs the full psychosocial history. Standard procedure. I get it.

Here's the problem: my psychosocial history is complex; basically it is a bingo card of Adverse Childhood Experiences. And in other risk categories for bad treatment: I am an overweight woman without "normal" insurance.

I've got decades of different psychiatric diagnoses and what turned out to be undiagnosed Multiple Sclerosis impacting my cognitive and behavioral life in very noticeable ways. It was a huge blessing that in 2013 I had a psychiatrist who noticed the pattern of very valid causes of my crashouts and noted the relationship between seasonal heat and a cognitive degradation.

But for years prior to that my neurological symptoms got shunted into the psych category because my childhood was a nightmare and I had the PTSD diagnosis to prove it. Fatigue that didn't improve with antidepressants? Depression. The cognitive symptoms: brain fog, word-finding problems, executive function collapse: all attributed to trauma response. Anxiety that wouldn't respond to SSRIs? Treatment-resistant psychiatric disease.

Turns out my brain has some autistic neurology and has been having holes burned into it by my immune system. Literal demyelinating lesions. For decades.

But nobody looked because I had the wrong kind of history and everything got swept under a rug after I did enough therapy that I no longer qualified for a PTSD label; thanks to being diligent about therapy and hungry to address the issues holding me down and back in this world.

And in 2025 we're well past the 10-year medical record retention limit US states have. I'm a blank slate and my medical life has to reboot with zero resources, which means I am at the mercy of random overworked clinicians finding me trustworthy.

Am I going to end up in a situation again, where I am a fucking raccoon digging through trashcan diagnoses to seek the truth and relief yet again while I look for a safe, clinical setting to grant me relief to some of the inconvenient as fuck anxiety issues my brain inflicts on life?

The Pattern Recognition Problem

I've learned not to be believed. That's the pattern I've internalized over 28 years of diagnostic delay. God willing there's no brutal cycle of veracity being tested with clinical trauma. Again.

So when I sit down for intake interviews now, I'm doing this fucked-up calculation. How much do I disclose? If I mention the childhood stuff, does that color how they interpret my current symptoms? If I don't mention it, am I withholding relevant medical history?

By my reasoning: withholding is a kind of lying in a lot of contexts and it is not productive to avoid truthfully answering about the kinds of abuse my mother and her accomplices carried out. If more of my teachers and community members had been aware, some incidents could have made the news.

I mention the trauma history because it's medically relevant. But I watch their face when I do. It hurts me to make them uncomfortable when I talk about kindergarten.

And I can see the moment my credibility shifts. Suddenly I'm not a patient with complex medical history. I'm a patient with psychiatric history reporting physical symptoms. The symptoms don't change. The MS lesions don't disappear from the MRI. But the frame changes.

The Cognitive Load

The September 2025 flare got me diagnosed. Vision loss. ER trip. Finally someone looked at my brain the right way.

The cognitive damage since then is real. Executive function. Processing speed. Working memory. I'm not wholly who I was before September even after I have bounced back a tiny bit from being the stuttering wreck that could barely walk.

I know my timeline. I've written about it diligently since September as I coalesce it into a memoir. A monument to my sense of freedom as the missing piece got diagnosed.

The facts are consistent because these things happened: I am an autistic trauma survivor with a history of PTSD and Generalized Anxiety Disorder. But reciting it over and over to strangers who are deciding whether to believe me? While I'm trying to gauge how much to disclose without tanking my credibility? That's exhausting.

I conducted the most recent one as a sloppy autistic bitch who's sick of masking. Just exhausted. Couldn't perform neurotypical anymore even if I wanted to. The cognitive energy isn't there.

The Exhaustion

I'm so fucking tired.

Tired of explaining. Tired of managing how my history gets received. Tired of watching for the shift in their expression when I mention certain events. Tired of doing damage control in real-time while also trying to give them accurate medical information.

The system demands this. Every new provider needs the intake. But the system doesn't account for what it costs to do this over and over when your history makes clinicians skeptical and your cognitive function is compromised by the disease they didn't catch for three decades.

There's no good solution. I can't not do the intakes. But every one feels like an audition for my own credibility.

I'm doing it anyway. Because I need the care. But this isn't just paperwork. This is trauma on top of disability on top of medical neglect playing out in real-time in a 50-minute appointment where I'm trying to sound coherent enough to deserve treatment.

I am an autistic trauma survivor with a history of PTSD and Generalized Anxiety Disorder, I'm proactive about seeking care for these issues especially when they become disabling. Oh and it turns out that also I have a Real, Physical Problem called MS that impacts me cognitively which in turn emotionally impacts me.

And of course I told my neurologist how disturbing, if not terrifying, the 2025 cognitive degradation is to me after a life spent surviving by wits alone.