Using Claude Cowork to Map Out Seasonal Allergies
Ethan Holland · April 2025
For over a decade, I've been tracking my health, fitness, and allergies, and I've noticed that from late February through early April, I have really bad sinus issues. I've tracked everything on a spreadsheet, and I note when I start my medicines, and every year I get a little better. This is the first year I've actually successfully navigated the allergies. I started Flonase on March 1, and I wear a KN95 mask when I'm outside, and I take Allegra.
Usually my symptoms end in mid-April, before the yellow pollen shows up. That has always confused me. The yellow pollen is not what gets me... it's something earlier. In an effort to try out Claude Cowork, I gave a very simple prompt, and I asked Claude to create a diagram or visual that would help me with my allergies, because I'm trying to pick a date when I'll stop wearing my mask and start going outside again.
Below, I've shared a few screenshots from 2018, 2019, 2022, and 2025 showing how I've tracked my health. I've also included the prompt that I gave Claude Cowork. Below this, you'll see the interactive website that Claude created for me in about a minute. It was a lot of fun to watch it do something that I would not have taken the time to do, but that has value to me personally. If you have not tried Claude Cowork, I highly recommend it.
💬 The prompt I gave Claude Cowork
I live in Ocean City, Maryland, and I suffer from pretty severe seasonal allergies. The allergies tend to manifest through a persistent cough. The cough usually starts in mid to late March. This year I've managed to mitigate a lot of the problems by starting Flonase right in the beginning of March, which gives me a two- or three-week head start on my allergies. And then around the second week of March, I start wearing a KN95 mask whenever I'm outside. I also take an antihistamine. This year, Allegra really seemed to work.
In the past, in late March, I would start getting sick around March 20th, and by the middle of the week, maybe March 24th, I would be miserable and I would cough to the point of coughing every 30 seconds for four days and not be able to sleep. The coughing usually persists until the end of March or the beginning of April. I'd love to understand what type of allergies occur in Ocean City at that point because that bright yellow pollen hasn't really kicked in at that point.
I'd like to get a table or a graph of some sort showing the peaks of allergy season a little more scientifically than just my own symptoms. I want to know what I'm up against, and especially I want to know when I can remove my mask and start to go outside. So my goal here is to build an understanding of what kind of allergies I'm experiencing, and then also an idea of the seasonal calendar so I can visualize my return to the outdoors.
What's Attacking You in Late March
🌲 The Invisible Villain: Eastern Red Cedar (Juniperus virginiana)
That yellow pollen that coats everything? That's Pine — and it doesn't show up until May. What's hammering you in late March is
Eastern Red Cedar, an extremely common juniper native to the entire Eastern Shore. Its pollen is a fine,
yellowish-tan dust — barely visible — that peaks in late February through late March.
It's one of the most potent allergenic trees in the Mid-Atlantic, and the Ocean City/Maryland coastal region is dense with it.
This is almost certainly your primary trigger. The good news: once you cross into April, cedar season is largely over.
Primary Offenders: Late March Window (Mar 15 – Apr 5)
Ordered by likely impact on your symptoms
🌲
Eastern Red Cedar / Juniper Primary Culprit
Juniperus virginiana — everywhere on the Eastern Shore. Peaks late Feb – late March. Pollen is light tan/orange, very fine, highly allergenic. Triggers rhinitis, persistent cough, and "cedar fever" symptoms.
🍁
Red Maple & Silver Maple Major Trigger
Acer rubrum / Acer saccharinum — blooms February through late March. One of the earliest tree pollinators. Very common in coastal Maryland. Overlaps directly with your worst weeks.
🌳
Elm Contributing Factor
Ulmus spp. — blooms February through March before leaves appear. A frequent early-spring allergen throughout the Mid-Atlantic.
🌿
Birch Rising in Late March
Betula spp. — starts late March, peaks through April. Highly cross-reactive with many food allergies (oral allergy syndrome). Likely adding to your late-March pile-on.
🌱
Ash & Alder Background Level
Early-season trees that contribute modest amounts of pollen in late March but are secondary to cedar and maple in the Ocean City area.
✅ Your Flonase Strategy Is Scientifically Sound
Starting Flonase in early March gives it 2–3 weeks to build up corticosteroid levels in your nasal passages before cedar and maple hit their late-March peaks. That head start is the difference between miserable and manageable. Allegra (fexofenadine) is a non-sedating H1 antihistamine with strong evidence for tree pollen — a solid match for your trigger profile.
Ocean City Pollen Species — Detailed Calendar
February
Alder, Red Maple, Elm starting to release. Low overall counts but sensitive people begin noticing. Cedar warming up.
March (your crunch time)
Eastern Red Cedar peaks. Maple at full force. Elm still active. Birch begins. Counts can hit Very High on warm dry days. This is your window.
April (the big one)
Oak explodes — the dominant allergen of spring. Birch peaks. Hickory, Ash, Mulberry active. Cedar fades. This is the highest total pollen month.
May (the yellow one)
Pine pollen appears — this is the visible bright yellow dust coating everything. Actually less allergenic than oak, but overwhelming in volume. Oak still active. Grasses begin.
June–July
Tree pollen mostly done. Grasses (Timothy, Orchard, Bermuda) peak. Ocean breezes at OC help moderate counts vs. inland. Generally your best outdoor months.
August–October
Ragweed season. Peaks in September. Also: mold spores peak with fall leaf decay. If ragweed bothers you, watch September carefully.
