You know this week if you live and work in the South Bay. The headache started Tuesday afternoon. Your eyes felt gritty by Wednesday. By Thursday you couldn't tell whether your stuffy nose was allergies, the office AC, or the dry air in your apartment. You finished standups, you cleared your PR review, you went to bed at 11:30 wondering whether to call your doctor.

Late May is the hardest stretch of this in the South Bay. Three things stack on each other in San Jose, Sunnyvale, Mountain View, and Cupertino.

Pollen. Oak pollen tails off but grass pollen ramps up. Bermuda, fescue, and rye drive symptoms across the South Bay through May into June.

Screens. The average tech worker spends nine to eleven hours a day at displays. Multiple monitors. Phone. Tablet. Often in dry, air-conditioned indoor air.

Air quality. Fire season hasn't started, but it's coming. The South Bay has had recent summers where AQI from inland wildfire smoke made even short outdoor exposures uncomfortable. People stayed indoors more, which meant more screen time and more recirculated air.

The headache + eye irritation + congestion combo can come from at least four sources at once. Sorting it out alone is hard.

This is general information, not medical advice. If you have severe symptoms (sudden vision changes, the worst headache of your life, persistent fever), get medical care.

Digital eye strain

The American Optometric Association calls it computer vision syndrome. You might just call it Wednesday afternoon.

Symptom fingerprint:

Eyes tired, gritty, or burning. Worse at end of day.
Intermittent blurred vision, especially when shifting focus from screen to far away
Headache that builds through the day, around the forehead or temples
Neck, shoulder, or upper back ache
Eyes that need to "reset"

Screen focus drops your blink rate, sometimes by half. Less blinking means a less stable tear film, so the eye surface dries out. Holding the same focal distance for hours fatigues your focusing muscles.

Try these:

The 20-20-20 rule. Every 20 minutes, look at something 20 feet away for 20 seconds. Set a recurring reminder. You won't remember on your own.
Preservative-free lubricating eye drops for frequent use. They rehydrate the tear film.
Monitor positioning. Top of screen at or below eye level, arm's length away. A second monitor stacked vertically often beats side-by-side for neck strain.
Lighting. Reduce window glare and overhead glare. Consider a matte screen filter.
Humidity. South Bay indoor air with AC running is dry. A small desk humidifier fixes a surprising amount.

If your symptoms persist through all of that, see an optometrist. A low-power prescription change or computer glasses can help, and an exam rules out other causes.

Allergic conjunctivitis

Symptom fingerprint:

Itchy eyes (this is the differentiator: eye strain feels tired or burning, allergies feel itchy)
Both eyes, about equally
Watery, slightly puffy lower eyelid
Often paired with sneezing, runny nose, or itchy throat
Worse on high-pollen days, better in clean indoor air
Improves with antihistamines or antihistamine eye drops

Try these:

Track the pollen. AirNow.gov and local pollen trackers show when South Bay grass counts spike.
Antihistamine eye drops (ketotifen, available OTC) often beat oral antihistamines for eye-specific symptoms.
Rinse pollen off when you get home. Change clothes, rinse your face, splash your eyes with cool water.
Run HEPA filtration indoors during high-pollen stretches, especially in the bedroom.
Close windows during peak pollen times (mid-morning on warm, dry, windy days).

Sinus pressure, tension headache, migraine

"Sinus headache" is the most over-diagnosed headache type. Most headaches that feel like sinus headaches are tension headaches or migraines wearing a disguise.

Tension headache fingerprint:

Dull, pressing, band-like pain around forehead or back of head
Mild to moderate
No nausea, no light or sound sensitivity
Often worse late in the day after long focus sessions

Migraine fingerprint:

Throbbing or pulsing, often one-sided
Moderate to severe
Sensitivity to light, sound, sometimes smells
Nausea or vomiting
Sometimes preceded by visual changes (aura)

True sinus headache fingerprint:

Real pressure or pain over the sinuses (cheeks, forehead, between or behind the eyes)
Discolored nasal discharge
Often a fever
Worse when bending forward
Almost always with clear signs of sinus infection

If your "sinus headaches" come without thick discolored discharge and don't improve once allergies are under control, they probably aren't sinus headaches.

Air quality and indoor environment

Indoor air in the Bay Area drives more symptoms than people realize, even before fire season starts.

Things worth knowing:

South Bay summer AC dries indoor air. Dry air worsens eye strain and irritates nasal passages, which mimics allergies.
Check AQI before outdoor exercise. AirNow.gov is the standard reference. Above 100 (Unhealthy for Sensitive Groups) matters if you have asthma or allergies. Above 150 affects everyone.
During smoke events, a well-fitted N95 or KN95 cuts particulate exposure outdoors. Cloth and surgical masks don't.
HEPA air purifiers running in your bedroom and office make a real, measurable difference on smoke days.

Quick wins this week

If you do nothing else from this article, do these five things:

Set a 20-20-20 reminder on your laptop.
Buy preservative-free lubricating eye drops. Keep them next to your keyboard.
Get a desk humidifier if you don't have one. Under $30 fixes a surprising amount.
Bookmark AirNow.gov. Check it on bad-feeling days.
If your "allergy season" symptoms are much worse than past years, see a doctor instead of stacking more OTC remedies.

Reasons to see someone

Most South Bay tech-worker symptom clusters resolve with the changes above. Signals that warrant a professional:

Optometrist: persistent eye discomfort that doesn't improve with breaks, drops, and screen adjustments. Any change in vision. Eye pain.
Primary care or allergist: allergy symptoms that don't respond to OTC antihistamines. A sudden new allergy pattern as an adult. Congestion lasting more than 10-14 days. Recurrent sinus infections.
Urgent care or ER: sudden severe headache (especially "worst of your life"), sudden vision change, facial weakness, high fever with sinus pain, any neurologic symptom.

A stacked cluster is hard to figure out alone

Eyes, head, sinuses, fatigue, all overlapping. Reddit threads from Sunnyvale show people spending weeks chasing one cause while the real driver was something else.

Symplicured is a free AI symptom checker for this kind of multi-symptom puzzle. Describe what you feel in plain language. Get a structured read on what your symptoms might mean and whether you need care. Start your assessment at symplicured.com/chat.