Lesson
Follow HSV From Entry to Reactivation
HSV replicates at a mucocutaneous site, enters sensory neurons, establishes lifelong latency, and can reactivate along the same neural distribution.
- HSV-1
- HSV-2
- Latency
- Reactivation
- Viral DNA polymerase
Local replication begins
Virus reaches the ganglion
No current eradication therapy
Prodrome can precede vesicles
Separate type from site
HSV-1 commonly causes recurrent herpes labialis, but either HSV type can infect oral or genital sites. Anatomy, exposure, and testing matter more than a type stereotype.
Establish latency
After local replication, HSV travels through sensory axons and persists in a ganglion. Current antivirals do not remove this neuronal reservoir.
Recognize reactivation
Illness, fatigue, stress, tissue trauma, dental work, hormonal change, and strong sunlight can trigger recurrence in susceptible patients, but triggers vary.
Target replication
Acyclovir and related nucleoside analogs require intracellular activation and inhibit viral DNA polymerase. Their value is greatest while viral replication is active.
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Lesson
Distinguish a Familiar Recurrence From a Dangerous Pattern
A typical recurrence is localized and familiar. Diffuse oral disease, eye symptoms, neurologic findings, immune compromise, and atypical lesions change the pathway.
- Prodrome
- Grouped vesicles
- Gingivostomatitis
- Keratitis
- Differential
Grouped vesicles near the lip
Fever and impaired intake
Diagnosis changes treatment
Protect sight and life
Recognize recurrence
Tingling, itching, burning, or pain often precedes grouped vesicles near the vermilion border. Lesions rupture, ooze, crust, and usually heal without scarring in an immunocompetent patient.
Recognize primary disease
Primary oral HSV can produce diffuse painful gingivostomatitis, fever, lymphadenopathy, odynophagia, and reduced intake, especially in children.
Protect the eye and brain
Eye pain, photophobia, visual change, gritty tearing, severe headache, confusion, seizure, or focal neurologic findings require urgent evaluation.
Keep the differential open
Aphthae, impetigo, angular cheilitis, contact dermatitis, trauma, candidiasis, hand-foot-and-mouth disease, and malignancy can mimic parts of the course.
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Lesson
Break Transmission Without Promising Zero Risk
Active lesions and secretions raise transmission risk, but HSV can also shed without visible disease. Precautions reduce risk rather than eliminating it.
- Contact
- Secretions
- Asymptomatic shedding
- Autoinoculation
- Hand hygiene
Avoid during outbreaks
Do not share
Wash after contact
Risk reduction is not zero risk
Avoid high-risk contact
During an outbreak, avoid kissing, oral contact, and sharing drinks, utensils, towels, razors, cosmetics, or lip products.
Control hand transfer
Do not pick lesions. Wash hands after touching a lesion or applying medication, and keep contaminated fingers away from eyes, genital skin, broken skin, and other people.
Explain shedding
Visible healing lowers risk, but appearance cannot prove that viral shedding has stopped. A lack of lesions does not guarantee zero transmission.
Protect vulnerable contacts
Newborns, immunocompromised people, and children with atopic dermatitis can develop serious disease. Contact precautions and early clinical advice matter.
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Lesson
Treat at the Prodrome, Not at the End of the Episode
Topical products provide modest benefit when started early. Site, age, immune status, schedule, and application burden determine whether they fit.
- Docosanol
- Acyclovir cream
- Penciclovir
- Early treatment
- Application technique
Start immediately
Five times daily until healed
Continue four days
Follow exact product label
Use docosanol within its label
Current OTC docosanol 10 percent labeling treats external cold sores on the face or lips. Apply five times daily from the first tingle, redness, bump, or itch until healed, following the exact product age and warning language.
Use acyclovir cream correctly
Acyclovir cream is for recurrent herpes labialis on the lips and around the mouth in immunocompetent patients at least 12 years old. Keep it out of the eye, mouth, and nose.
Plan penciclovir frequency
Penciclovir 1 percent cream is applied every two hours while awake for four days and should begin at the earliest sign. The frequent schedule and modest average benefit must be understood.
Prevent contamination
Use clean hands or a clean cotton-tipped applicator, dab rather than scrub, wash hands afterward, and do not share the product.
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Lesson
Select an Antiviral Regimen by Indication
Oral and buccal therapies can improve convenience and efficacy, but cold sore regimens cannot be borrowed from genital herpes or zoster.
- Valacyclovir
- Acyclovir
- Buccal tablet
- DNA polymerase
- Indication-specific dosing
Verify renal table
Inhibits viral DNA polymerase
Apply within one hour of prodrome
Balance benefit and burden
Use the labeled valacyclovir course
A current label uses valacyclovir 2 grams every 12 hours for one day in adults and patients at least 12 years old. Start at the earliest symptom and do not exceed one day for this indication.
Understand prodrug pharmacology
Valacyclovir is converted to acyclovir and improves oral bioavailability. Intracellular acyclovir triphosphate inhibits viral DNA polymerase and terminates DNA-chain elongation.
Use buccal acyclovir as designed
Acyclovir 50 mg buccal tablet is a single dose for immunocompetent adults, placed on the upper gum canine-fossa region within one hour of prodrome. Do not crush, chew, suck, or swallow it.
Choose route deliberately
Consider onset, recurrence burden, renal function, immune status, swallowing, application burden, access, expected modest benefit, and preference.
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Lesson
Connect Renal Clearance to Dose and Toxicity
Acyclovir exposure rises when renal clearance falls. Hydration, dose adjustment, nephrotoxins, age, dialysis, and immune status shape safety.
- Creatinine clearance
- Acute kidney injury
- Neurotoxicity
- Hydration
- Severe reactions
Adjust the indication-specific dose
Respect heart and kidney limits
Consider accumulation
Standard self-care evidence may not apply
Calculate renal function
Use the current product label and the institution's accepted renal estimate. A normal-looking serum creatinine can hide low clearance in an older or low-muscle-mass patient.
Protect the kidney
Dehydration, excessive dose, rapid high exposure, existing kidney disease, and nephrotoxins increase acyclovir crystal nephropathy and acute kidney injury risk.
Recognize neurotoxicity
Confusion, agitation, hallucinations, tremor, myoclonus, or seizures during treatment can reflect accumulation and require urgent evaluation.
Escalate serious host and skin findings
Current valacyclovir labeling includes severe cutaneous reactions and TTP or HUS in specific severely immunocompromised high-exposure settings. Rash with mucosal or systemic illness, hemolysis, thrombocytopenia, or renal decline needs prompt care.
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Lesson
Support Healing Without Damaging the Barrier
Comfort measures and trigger reduction can help, but caustic remedies and unproven supplements can delay effective care.
- Cool compress
- Pain relief
- Lip barrier
- Sun trigger
- Lysine
Support comfort
Avoid picking
Useful when sunlight is a trigger
Do not replace proven care
Use gentle comfort care
Cool compresses, bland lip protection, adequate intake, and age-appropriate analgesia can improve comfort. Avoid picking or peeling the crust.
Avoid tissue injury
Alcohol, bleach, acids, aggressive exfoliation, and other caustic home remedies can worsen pain, delay healing, and obscure secondary infection.
Address sunlight triggers
For patients with sun-triggered recurrences, use broad-spectrum SPF 30 or higher lip balm and layered photoprotection. Do not promise complete prevention.
Counsel on supplements honestly
Lysine is commonly used, but current evidence does not establish it as a reliable substitute for antiviral treatment or suppression. Review product quality, cost, interactions, and kidney or reproductive considerations.
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Lesson
Escalate by Burden, Host, and Complication
Frequency, severity, functional impact, immune status, atopic dermatitis, eye symptoms, duration, and infection determine prevention and referral.
- Suppressive therapy
- Eczema herpeticum
- Immune compromise
- Secondary infection
- Pregnancy and pediatrics
Consider suppressive planning
Test and treat earlier
Urgent systemic care
Know the red flags
Measure recurrence burden
Document episode frequency, duration, pain, missed work or school, triggers, psychosocial effect, and response. Frequent or disabling disease can justify clinician-directed suppression or pre-exposure therapy.
Recognize eczema herpeticum
Painful monomorphic vesicles or punched-out erosions spreading across atopic dermatitis, especially with fever or eye symptoms, require urgent systemic antiviral care.
Protect immunocompromised patients
Prolonged, extensive, atypical, resistant, or disseminated disease warrants testing, systemic therapy, and specialist input rather than routine self-care.
Use product-specific reproductive and pediatric evidence
Do not use retired pregnancy letters or adult self-care dosing for young children. Assess pregnancy timing, lactation, infant contact, age, weight, renal function, and exact labeling.
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Module test
Check the connections.
Each attempt draws 10 questions from the complete 112 question bank.
Each attempt draws a fresh set and rearranges the answer choices.
References
Current clinical foundation.
Lecture material was synthesized with the following contemporary guidance. Verify local policy and current guidance before applying clinical information.