How I Make Leadership Decisions on Brain Fog Days

My joints ache from another restless night with Ehlers-Danlos Syndrome (EDS), and I can feel a Mast Cell Activation Syndrome (MCAS) flare building. Both conditions are fueling my brain fog. I’m staring at a Slack message, and I can’t make sense of it. I’ve read the same sentence four times, but the words won’t stick. This is the reality I’m navigating as I make a decision that can’t wait, and it’s one that many other leaders face regularly as well.

What My Brain Fog Feels Like With EDS and MCAS

Brain fog isn’t just feeling tired or distracted, though that’s often the case. It’s a set of cognitive symptoms that includes difficulty concentrating, confusion, forgetfulness and more. When you’re living with a chronic condition, such as my EDS and MCAS, brain fog becomes a part of managing your workday. 

EDS can contribute to fatigue, and poor sleep can make that fatigue worse. This cycle can fuel my fog. Yesterday, I had a major strategy meeting scheduled after a night of waking up every 90 minutes, which compounded the fatigue I already manage. By the time the meeting started, my brain felt like it was moving through water.

Meanwhile, MCAS flares cloud my thinking. It can affect your brain and nerves, causing confusion, difficulty processing information and trouble remembering what was just said. Nearly 9 in 10 women with MCAS report this same fog, according to a 2025 study. 

How I Manage My Brain Fog and Run a Business 

Running a business means I need to make decisions whether my brain is cooperating or not, so I’ve built three practices that protect both my company and capacity.

Saying No to Extra Work on My Foggiest Days

If I wake up feeling unrested, notice light or sound sensitivity, or have trouble breathing and swallowing, I know my capacity is lower. On those days, I run tasks through these three questions:

• Does this require a decision I can’t reverse? If yes, I push it to a clearer day. 
• Does this require me specifically? If someone else can execute it just as well, I delegate. 
• Is this time-sensitive, or can it wait 24-48 hours? If it can wait, I let it wait.

Based on a 2026 survey, over one-third of workers say it’s too much work that harms their mental health the most. Learning to say no on foggy days protects both your well-being and the quality of your work. Here are tips to build that boundary into your workday:

• Pre-approve your “No” list: Write down the categories of work you’ll decline or delegate when foggy, so you don’t have to make that call in the moment.
• Name a standing backup: Designate one person as your default delegate in advance, so you already know who to hand things to.
• Keep a one-line script ready: Have a pre-written message for declining or delaying work to avoid having to compose explanations from scratch while foggy. 

Building My Toughest Decisions Around My Clearest Hours

I track my mental clarity at set check-in points during the day, rating how sharp I feel on a scale of one to five. After a few weeks, I can conclude my clearest window is 10 a.m. to noon, after breakfast.

Now, I timebox that window for high-stakes decisions. I set my booking tool so important calls can only land during those hours. Everything else goes into a decision queue that I process once I hit my window.

If you’re establishing this practice for yourself, remember that if your clear window disappears on a given day, you should push the decision back rather than forcing it into a foggy hour. If a decision truly can’t wait, ask yourself whether you’d make this same call if you weren’t foggy right now. If you’re unsure, say so out loud rather than deciding in silence.

Creating Simple Systems So My Business Doesn’t Depend on a Clear Head

Companies only have 15%-20% of their knowledge documented, which means critical processes often live in one person’s head and disappear the moment that person is unavailable. I don’t want to be that single point of failure, so I’ve built systems.

I have a written procedure for onboarding clients that allows anyone on my team to follow the steps without asking me, and I keep a decision log where key choices and their reasoning are recorded as they’re made, so future me doesn’t have to reconstruct the context. 

To identify where you need systems, track which tasks take the longest or feel most draining on your foggiest days, and start with those. 

Your Brain Fog Doesn’t Disqualify You From Leading

You’re not broken because you have foggy days. You’re strategic because you’ve learned how to lead through them. Leadership is every boundary you set, every system you build and every decision you make in your clearest hours.