infectious

Herpes labialis (cold sores)

Treatment options, dosing, cautions and Egyptian brands from the shipped Dawaa Reference card.

Evidence status

Checked against the sources named below

Sources1 source

Egyptian National Drug Formulary - Antimicrobial 2023 (acyclovir monograph)

Verified against1 document

Egyptian National Drug Formulary - Antimicrobial 2023 (acyclovir monograph)

Verified date2026-08

Presentation reference

Is it this?

Reference only, to read alongside your own examination.

Symptoms — what the patient reports (6)

Most oral HSV-1 infection causes no symptoms; when it does, the usual result is a cold sore
A first attack starts three days to a week after exposure
Before the blisters there is a prodrome of malaise, no appetite, fever, sore glands, and local pain, tenderness, burning or tingling [blisters · fever · local tenderness · malaise · tingling]
In children a first attack often takes the form of gingivostomatitis with pain, bad breath and difficulty swallowing [difficulty swallowing]
In adults it can look like pharyngitis or a glandular-fever-like illness [fever]
Recurrences are milder, heralded by about a day of tingling, burning and itch [itching · relapse · tingling]

Signs — what you find (12)

First attack sits on the mouth and lips: painful clustered blisters on a red base with a scalloped edge, becoming pustules, erosions and ulcers [blisters · pustules]
Lesions crust and the episode settles within 2 to 6 weeks
Recurrent attacks classically sit on the lip margin, not spread across the mouth and lips as the first one does
Herpetic sycosis: beard-area follicular papules with erosion in a man who shaves closely, from scattered spots to the whole beard, clearing in 2 to 3 weeks [papules]
Herpes gladiatorum: lesions on the side of the neck and face and on the forearms 4 to 11 days after contact, easily mistaken in athletes for bacterial folliculitis
Herpetic whitlow: deep blisters on a finger or around the nail that erode, often mistaken for acute paronychia or blistering dactylitis [blisters]
Whitlow can enlarge elbow or armpit nodes with red streaking that imitates cellulitis [cellulitis]
Eye disease: keratoconjunctivitis in one or both eyes with tearing, lid swelling, light sensitivity, a swollen conjunctiva and a node in front of the ear [eye discharge · eyelid swelling · photophobia]
A branching dendritic corneal ulcer is diagnostic of ocular herpes, and this keratitis is a leading cause of blindness [loss of vision]
Red flag: strange behaviour, focal temporal-lobe signs, fever and altered consciousness suggest herpes encephalitis, fatal in over 70% untreated [fever]
Eczema herpeticum: widespread punched-out erosions of 2 to 3 mm with bloody crusts, on skin already damaged by eczema or similar disease
Newborn herpes shows at day 5 to 14 on scalp and trunk, may spread over the skin and to mouth and eye, and brain involvement brings lethargy, poor feeding, a bulging fontanelle, irritability and fits [bulging fontanelle · irritability · lethargy · poor feeding · seizures]

Tests (3)

Antibody testing by western blot is the reference standard, while viral PCR is the most sensitive and specific method
Other options are viral culture, direct fluorescent antibody and Tzanck smear
A Tzanck smear only shows multinucleated giant cells and cannot separate herpes simplex from varicella zoster; the fluorescent antibody test can

If not this — what else fits (6)

Aphthous stomatitis
Stevens-Johnson syndrome
Erythema multiforme major
Herpangina
History and examination are what separate these from oral herpes
For a finger lesion: blistering dactylitis, and acute or chronic paronychia

SourceStatPearls "Herpes Simplex Type 1" - disease-level clinical article

Presentation findings are traced to the source above.

ACYCLOVIR

1st line

Formtopical

Adult dose and duration

Apply 5 times daily (every 4 hours) to affected skin x 4 days

Paediatric dose

Topical cream: Apply 5 times daily for 4 days in immunocompetent children ≥12 years of age

Dose source

Egyptian National Drug Formulary - Antimicrobial 2023 (acyclovir monograph)

Why

Nucleoside analogue antiviral that is selectively activated in infected cells to block viral DNA replication, applied topically at the first sign of a cold-sore recurrence to shorten the episode.

Cautions

Apply at first sign of prodromal tingling or redness.
Wash hands before and after application to prevent autoinoculation.
Avoid contact with eyes.

Egyptian brands

Egyptian brand	Manufacturer	Indicative price
VIRUSTAT 5% CREAM 5 GM	PHAROPHARMA	13.00 EGP
ACYCLOSTAD 5% CREAM 10 GM	GLOBAL NAPI PHARMACEUTICALS > STADA	23.00 EGP
ACYCLOVIR-MISR 5% TOPICAL CREAM 10 GM	MISR	23.00 EGP
VIRUSTAT 5% CREAM 10 GM	PHAROPHARMA	23.00 EGP
ZOVIRAX 5% TOPICAL CREAM 10 GM	GLAXO SMITHKLINE	27.00 EGP

Prices are indicative (dataset snapshot 2026-06); verify with the pharmacy.