Cold Sores

Cold sores: FAQs

Cold sores are small, fluid-filled blisters around the lips caused by the Herpes Simplex Virus (HSV-1). They typically clear up on their own within 7 to 10 days, but starting antiviral treatments at the very first tingle can significantly speed up recovery and reduce discomfort.

1. What causes cold sores?

Cold sores are caused by the Herpes Simplex Virus Type 1 (HSV-1) (and less commonly, HSV-2). Once you catch the virus, it stays dormant in local nerve pathways for life. It can reactivate and trigger a cold sore whenever your immune system is temporarily taxed or your skin is irritated.

Common triggers include:

  • Stress or exhaustion

  • Sunlight (UV exposure) or cold wind

  • Fever, cold, or flu

  • Hormonal shifts

  • Lip injury or chapping

2. What are the stages of an outbreak?

An outbreak usually moves through five distinct phases:

  1. Tingle / Prodrome (Days 1–2): Itching, burning, or tingling around the lips before anything is visible.

  2. Blister (Days 2–4): Small, painful fluid-filled bumps cluster along the lip boundary.

  3. Weeping / Ulcer (Day 4–5): The blisters burst, leaving shallow open sores. This is the painful and most contagious stage.

  4. Crusting (Days 5–8): The sores dry out and scab over.

  5. Healing (Days 8–10): The scab shrinks, flakes off, and skin fully repairs without leaving a scar.

3. How contagious are cold sores, and how do they spread?

They are extremely contagious. The virus spreads through direct skin-to-skin contact (like kissing) or shared items (towels, lip balms, eating utensils, drinking glasses).

  • When are they most contagious? From the moment you feel the first tingle until the sore is completely scabbed over and healed.

  • Safety Tip: Avoid touching the sore. If you touch an active cold sore and then touch your eyes, you can cause a painful eye infection called herpetic keratitis. Always wash your hands thoroughly after applying creams or touching your face.

4. How can I treat a cold sore and speed up healing?

While there is no permanent cure to erase the dormant virus, you can treat active flare-ups:

  • Topical Antivirals (OTC): Creams containing Aciclovir or Docosanol stop the virus from replicating. They work best when applied at the very first tingle (prodrome stage).

  • Hydrocolloid Patches: Discreet patches cover the sore, shield it from secondary bacterial infection, reduce scabbing, and minimize viral shedding.

  • Prescription Oral Antivirals: Oral tablets (such as valaciclovir or aciclovir) prescribed by a doctor or pharmacist offer a stronger, systemic response that can drastically shorten severe or frequent outbreaks.

  • Symptom Relief: Over-the-counter pain relievers (ibuprofen or paracetamol) ease inflammation, while cold compresses reduce local pain.

5. Can I prevent outbreaks from happening?

While you can't eliminate the virus, you can reduce how often it flares up:

  • Apply an SPF 30+ lip balm before going out in strong sunlight or cold wind.

  • Maintain a healthy sleep schedule and manage stress levels.

  • Avoid sharing personal items like towels, lip products, or cutlery—even when you don't have an active sore, as mild "asymptomatic shedding" can still occur.