Blog · Accessibility

Reading online health information with dyslexia

12 min read · July 30, 2026

Most online health content is formatted for a general audience in a hurry. Long words, dense paragraphs, serif body text at 14px, and cluttered layouts built around advertising slots. For dyslexic readers, that combination turns what should be a quick check of your test results or a medication dosage into something genuinely exhausting — and the stakes are higher than they are for, say, a news article or a recipe.

This guide covers the specific challenges health sites present, which browser and font settings reduce them most, and how to build a setup you can apply to any health website without per-site configuration.

Why health sites are particularly hard to read

Most text on the web is hard to read with dyslexia. Health sites layer on several additional difficulties that are specific to the domain.

Long, unfamiliar words with similar letter sequences. Medical terminology is full of words like "contraindication," "thrombocytopenia," or "antihypertensive" — long strings where a dyslexic reader's tendency to transpose letters or lose track mid-word is most costly. Getting "metformin" and "metronidazole" mixed up matters in a way that confusing "beautiful" and "bountiful" typically does not.

Numerical information embedded in dense text. Drug dosages, reference ranges, test results — these arrive as numbers surrounded by prose, and the numbers are the point. Readers who also have dyscalculia (which co-occurs with dyslexia at a rate higher than chance) are at double risk of misreading "1.5 mg" as "15 mg" or reading "every 8 hours" as "every 18 hours."

Serif fonts and small type. The NHS website, WebMD, Mayo Clinic, and most patient portals have improved their typographic choices in recent years, but plenty of pages — especially drug information leaflets rendered as HTML, clinical summaries, and older institutional portals — still use Times New Roman or small Georgia at tight line spacing. These are among the most demanding rendering conditions for dyslexic readers. See our piece on serif vs sans-serif for dyslexic readers for the research behind that.

Ad-laden, multi-column layouts. Consumer health sites like WebMD, Healthline, and Verywell Health generate revenue from advertising. That means sidebars, interstitials, and content recommendations competing with the text you actually need. For dyslexic readers, visual clutter is not just annoying — it actively disrupts the ability to track a line of text and hold context across a paragraph.

Anxiety as a compounding factor. When you're reading about a diagnosis, a medication you've just been prescribed, or a test result you don't understand, you're doing it under stress. Anxiety reliably worsens reading performance for everyone. For dyslexic readers, who already expend more cognitive effort on decoding, the combination of difficult text and emotional load is a meaningful accessibility problem, not a minor inconvenience.

Which fonts reduce the difficulty most

The fonts that help most for health content are the same ones that perform best for dense, technical text generally — but the priorities shift slightly. You want clarity at the letter level more than you want reading speed. When every word matters, slower and more accurate beats faster and error-prone.

Atkinson Hyperlegible was specifically designed by the Braille Institute of America to maximise legibility for people with low vision and reading difficulties. Its distinguishing feature is that it maximises the visual distinction between easily confused characters — not just b/d/p/q but also I/l/1, O/0, and rn/m (a pair that trips dyslexic readers far more often than most typography resources acknowledge). For medical text where those confusions have real consequences, Atkinson Hyperlegible is worth trying before anything else.

Lexend was developed specifically to reduce visual stress and improve reading fluency. Its generous letter spacing and moderate x-height work well with the long compound words that appear frequently in health content. See our comparison of Lexend vs Atkinson Hyperlegible if you're deciding between them.

OpenDyslexic is the right choice if letter rotation (b/d, p/q) is your primary difficulty. For health text, this matters most with abbreviations and numeric notation where rotated characters are hardest to catch from context.

Here is the same excerpt of text rendered in two different ways — the kind of typography you might encounter on an older patient portal versus a tuned browser setup:

Typical patient portal typography (Times New Roman, 14px, tight) Take metformin hydrochloride 500mg twice daily with meals. Do not exceed 2000mg per day. Contraindicated with renal impairment (eGFR below 30 mL/min/1.73m²). Report any symptoms of lactic acidosis including muscle pain, difficulty breathing, or unusual drowsiness immediately.

Same text in Atkinson Hyperlegible, 17px, 1.7 line height Take metformin hydrochloride 500mg twice daily with meals. Do not exceed 2000mg per day. Contraindicated with renal impairment (eGFR below 30 mL/min/1.73m²). Report any symptoms of lactic acidosis including muscle pain, difficulty breathing, or unusual drowsiness immediately.

The content is identical. The cognitive demand is not. The Atkinson Hyperlegible version gives each letter room to breathe, and the generous line height reduces the risk of losing your place and re-reading the wrong line — a mistake with real consequences when the text is about dosages.

Browser settings that make the biggest difference

Font choice is the most impactful single lever, but it is not the only one. These browser-level settings each address a distinct part of the problem.

Increase the base font size. Chrome's default font size is 16px. For health content, 18–20px is a better baseline. Go to Chrome Settings - Appearance - Font size and set it to Large or Very Large. This applies across all sites unless a site's CSS explicitly overrides it (many health portals do, which is where a font override extension becomes essential).

Set a minimum font size. In Chrome Settings - Appearance - Customise fonts, there is a minimum font size slider. Setting this to 14 or 15px prevents sites from displaying footnotes, disclaimers, and dosage tables in type so small it is unreadable regardless of font family.

Increase line height. Standard body text on most health sites sits at 1.4–1.5 line height. A dyslexia-friendly reading setup uses 1.6–1.8. This is harder to change globally via browser settings than font size, but a font-override extension like LexiFont applies generous line height alongside the font change, so you get both adjustments at once. The research on line spacing and letter spacing for dyslexia consistently shows this as one of the most effective typographic interventions.

Use a warm or cream background. High-contrast black-on-white is not always the most comfortable background for dyslexic readers, and for health content read under stress it can worsen visual crowding. A slightly warm off-white reduces glare without hiding detail. See the evidence for this in our piece on background colours for dyslexia.

Consider dark mode carefully. Dark mode reduces overall brightness and can ease eye strain, but it reverses contrast polarity — white text on dark background — which some dyslexic readers find harder for long-form medical text. Our guide to dyslexia-friendly dark mode covers this in detail. The short version: test it on a page you know well, and pay attention to whether you start re-reading lines more often than you do in light mode.

Handling reader mode on health sites

Chrome's built-in reading mode (available under the Reader Mode flag or as a side panel on recent versions) strips most advertising and layout clutter from articles. On consumer health sites like Healthline or WebMD it works well, reducing a page from a cluttered column surrounded by ads to a clean single-column text view you can style with your preferred font.

Reader mode does not work reliably on all health sites. It tends to fail on:

Patient portals (MyChart, Patients Know Best, NHS App-linked sites) — these are web applications, not articles, and reader mode either strips out the structure you need (like test result tables) or fails to engage at all. For these, a font-override extension is the right tool rather than reader mode, because it applies to the live site without stripping its layout.

Drug information leaflets embedded as HTML tables — reader mode sometimes mangles these into a stream of text that loses the tablular structure. Again, a font override preserves the structure while changing only the typography. Our comparison of reader mode vs reading extensions for dyslexia covers when to use which.

Paginated result summaries — patient portals often present a list of test results across multiple panels and tabs. Reader mode cannot navigate these; you need to read the live page. LexiFont's font override applies site-wide and persistently, so every tab and panel of a portal session uses your chosen font without needing to be re-triggered.

Text-to-speech as a complement, not a replacement

For health content specifically, reading aloud while reading visually is worth considering even if you do not use text-to-speech generally. The redundancy — hearing the word while seeing it — significantly reduces the risk of misreading a dosage or an instruction. Having the word "contraindicated" spoken aloud makes it much harder to confuse with "indicated."

Chrome has a built-in "Read Aloud" feature in recent versions (right-click - Read Aloud on most pages). There are also dedicated extensions with better voice quality. Our guide to text-to-speech in Chrome for dyslexia covers setup in detail. For health content, even if you use TTS nowhere else, adding it for medication instructions, lab results, and discharge summaries is a practical safety measure, not a workaround.

A specific case where TTS matters. Drug instruction leaflets — the inserts inside medication packaging, now often available as HTML on pharmacy websites — are typically written at a reading age well above what the government recommends for patient information. Research in health literacy consistently finds that even adults without reading difficulties misread dosage instructions at meaningful rates. For dyslexic readers, the rate is higher. Running TTS alongside a font override for this specific content type adds a real safety layer at no extra cost.

Setting up a persistent health-site reading profile

The goal is a setup you do not have to think about. You should not need to manually adjust settings every time you open a patient portal or a health information page. Here is what a low-friction, persistent setup looks like.

Install LexiFont and set your preferred font to Atkinson Hyperlegible or Lexend (both available on the free tier). LexiFont remembers this preference and applies it to every new site you visit, including health portals, without any per-site action. When you open your NHS login or a MyChart session, the font is already in place before you start reading.

Set Chrome's minimum font size to 15px and base font size to Large in Appearance settings. This is a one-time change that persists across sessions.

If you use a specific patient portal regularly, consider enabling LexiFont Pro, which allows per-site font and layout customisation. You can set a larger font size, a cream background, and increased line height specifically for that portal's domain, so the moment it loads you have your optimal reading environment without any manual steps. The one-time cost of Pro is low relative to the cumulative time and stress saved across years of health appointments and test results.

Add Chrome's Read Aloud to your toolbar and get in the habit of triggering it on any page that contains numerical information — test results, dosage instructions, reference ranges. The habit is quick to build and the cognitive offloading is meaningful.

What to do when the site resists your settings

Some health portals use CSS that explicitly overrides browser font settings. They set font-family, font-size, and line-height in their stylesheets with enough specificity that Chrome's built-in font preferences do not reach through. A font-override extension applies at a different level — directly in the browser's rendering of the page — and can penetrate those overrides in most cases.

If you encounter a portal that still resists, the practical fallback is to use the browser's built-in zoom (Ctrl/Cmd and + or the View menu). Zoom scales everything proportionally and cannot be overridden by CSS. It does not change the font or improve letter spacing, but it does make every character larger and that alone reduces decoding errors significantly. Our work on font size for dyslexic adults gives the evidence base for why size matters independently of font choice.

For genuinely inaccessible portals — some older NHS trust patient portal systems and US Epic-hosted MyChart installations that have not been updated in years — consider requesting a paper printout of any information you need to retain. This is a legitimate reasonable adjustment to ask for under accessibility law in both the UK and US, and paper gives you the option to use a physical reading guide, coloured overlay, or magnifier that browser settings cannot replicate. Online tools can take you far; paper remains a practical backup for the hardest cases.

A note on understanding, not just reading

The harder problem with health information is not just decoding the words but understanding what they mean. Plain English summaries are not always available, and even when they are, the gap between the plain English version and the clinical document can leave important nuance on the table.

Reading more accurately — with a better font, at a bigger size, with TTS running — is a genuine improvement. It does not substitute for asking a pharmacist or GP to walk you through information you are unsure about, which is a straightforward request that healthcare professionals expect and welcome. The tools above reduce the effort of reading; they do not eliminate the value of a conversation when the stakes are high.

Similarly, working memory difficulties often accompany dyslexia and make it harder to retain a string of instructions even when you have read them accurately. Writing down key information — or copying and pasting it into a notes app where you can highlight and annotate — is a more reliable strategy than trying to hold it in memory after a single read. Most patient portals allow you to print or download your records, and the option to copy text from a browser page remains available on almost every health site.