Could this be hand-foot-and-mouth disease?

It can look similar in children. A swab distinguishes them, and that distinction matters for what to do next.

Is a first outbreak worse?

Often, yes — a primary infection can involve fever, swollen lymph nodes and extensive ulceration, especially in children. That deserves a clinician today.

Should I get a blood test?

If there is a visible sore, swab it instead. And decline IgM.

What Does Herpes in the Mouth Look Like? Stages, Photos & Testing

Medically reviewed by our MD Laboratory Director (a role required by CLIA; the director’s name is on file in the CMS CLIA database, #45D2048957, and can be verified independently) · Editorial policy

Herpes inside the mouth appears as clusters of small blisters that quickly break into shallow ulcers, and it has a strong preference for hard, keratinized surfaces — the gums and the hard palate. Canker sores do the opposite: they favour soft, movable tissue (inner cheek, under the tongue) and are usually single, round, white-grey with a red rim.

Have a sore right now? Swab it today while it is fresh — lesion PCR is the most reliable herpes test there is, and it loses sensitivity as the sore crusts over.
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📞 Call (713) 266-0808

3707 Westcenter Dr Suite 100, Houston, TX 77042 · Walk-ins welcome

Herpes lesions inside the mouth — **Intraoral HSV** — clustered vesicles breaking down into shallow ulcers.

Herpes vs. canker sore: the location rule

	Herpes (HSV-1)	Canker sore (aphthous ulcer)
Where	Hard tissue — gums, hard palate; and the lip border	Soft tissue — inner cheek, under tongue
Number	Clusters	Usually one
Starts as	Blisters, then ulcers	An ulcer from the start — no blister phase
Contagious	Yes	No
First episode	May come with fever and swollen nodes, especially in children	No systemic illness

The rule of thumb clinicians use: if it is on tissue you can move, it is probably not herpes. Not infallible — which is exactly why a swab exists.

Stages

Stage	What you see	Timing
Prodrome	Tingling, burning; nothing visible	Hours to a day
Blister	Clustered clear vesicles	Day 1–2 — best day to swab
Ulcer	Shallow, painful, weeping	Day 2–4 — most contagious
Crust / heal	Scab, then new tissue	Day 4–12

Do not accept an HSV IgM blood test. CDC does not recommend it — it generates false positives and unnecessary panic. If there is a sore, swab the sore. See lesion PCR vs. antibody testing.

We name drugs, never doses. Antiviral therapy for HSV follows CDC guidance; what you take is decided by a licensed physician who has examined you.

The single most useful thing on this page. If you have a sore right now, get it swabbed today — lesion PCR identifies HSV and types it (HSV-1 vs HSV-2). Sensitivity falls as the sore dries, so the best day to test is the day it appears. Sample by 1:00 PM → result at 4:30 PM → licensed partner-network physician 4:30–6:00 PM if treatment is clinically appropriate. Same day. Walk in, no appointment, no insurance. Text (713) 832-8892.

FAQ

Could this be hand-foot-and-mouth disease?: It can look similar in children. A swab distinguishes them, and that distinction matters for what to do next.
Is a first outbreak worse?: Often, yes — a primary infection can involve fever, swollen lymph nodes and extensive ulceration, especially in children. That deserves a clinician today.
Can I be treated the same day?: Yes — result at 4:30 PM, licensed partner-network physician 4:30–6:00 PM.
Should I get a blood test?: If there is a visible sore, swab it instead. And decline IgM.

The sore will crust over in a few days — and the test gets less reliable as it does.
Walk in today. Result at 4:30 PM. Licensed partner-network physician 4:30–6:00 PM if you need treatment. No appointment, no insurance — Save up to 40% compared to urgent care.
📱 Text (713) 832-8892 — fastest
📞 Call (713) 266-0808

3707 Westcenter Dr Suite 100, Houston, TX 77042 · Mon–Fri 9–5 · Walk-ins welcome · CLIA #45D2048957 · CAP #8722734

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