Cold sore on holiday in Spain? Here's what to do.

How to tell if it's a cold sore

Cold sores follow a fairly predictable pattern. If you have had one before, you usually recognise the early signs. If you have not, the sequence below tends to play out over a week or so.

• Tingling, burning, or itching at the edge of the lip, usually 24 to 48 hours before anything is visible. This is called the prodromal phase, and it is the most important moment for treatment.
• A small red patch appears, often slightly raised.
• Fluid-filled blisters develop over the next day, usually in a small cluster on the border between lip and skin.
• The blisters weep, then crust over after two or three days.
• The crust heals and the sore disappears, usually within seven to ten days from the first symptom.

Cold sores are caused by the herpes simplex virus, which most people pick up in childhood. The virus stays in the body for life and reactivates from time to time when something triggers it. On holiday, the usual triggers are stacked together: sun exposure, late nights, stress, alcohol, and being run down.

When you need to be seen in person

Most cold sores are uncomfortable rather than dangerous. A small number of situations need in-person assessment, not an online consultation. Go to Urgencias or your nearest Centro de Salud in any of the following cases.

For genuine emergencies — sudden vision change, severe facial swelling, or signs of sepsis — call 112.

What a Spanish pharmacy can do without a prescription

A Spanish farmacia will help with a cold sore quickly and without a prescription. What they can offer:

• Antiviral lip creams, applied at the first sign of tingling and continued through the active phase.
• Topical anaesthetic gels for the pain.
• Zinc oxide or sun-protective lip balms to limit further trigger from UV exposure.
• Hydrocolloid patches made specifically for cold sores, which protect the area and speed crust healing.
• Painkillers like paracetamol or ibuprofen.

For a typical cold sore caught early, the pharmacy answer is often enough on its own. Oral antiviral tablets, which are the strongest treatment, require a prescription in Spain and cannot be bought over the counter.

When an oral antiviral is worth getting

Topical antivirals make a modest difference. Oral antiviral medication makes a larger one — but only when it is started early, ideally during the tingling stage before any blister has formed. Once the cold sore is fully developed, the benefit of oral treatment falls off sharply.

Oral antivirals are particularly useful in three situations:

• Frequent recurrences — for example, more than five or six cold sores a year.
• Severe or unusually large cold sores that are painful or socially disruptive.
• An event you cannot move — a wedding, an interview, a long-anticipated holiday — where shortening the cold sore by a day or two is worth the consultation.

The choice of medication and the right dose depend on Spanish prescribing guidelines and on your personal history. That is a clinical decision and it happens during the consultation, not on a web page.

How to get a Spanish prescription the same day

Three routes, with the same trade-offs that apply to most non-urgent prescription needs in Spain.

Public route: Centro de Salud

With an EHIC, a UK GHIC, or a Spanish tarjeta sanitaria, any Centro de Salud will see you for non-urgent care. For a cold sore where timing matters — every hour you wait, the antiviral works a bit less well — the practical question is whether you can be seen today.

Private in-person GP

A private GP appointment runs around EUR 50 to 120, usually with same-day availability. English-speaking clinicians are common in cities and on the coast. You leave with a Spanish receta privada.

Online private consultation

A cold sore is the textbook case for an online consultation. The diagnosis is clinical and visual, the history is short, and an in-person examination adds little. Submitting a consultation in the prodromal phase is the fastest way to get treatment in your hand while it still makes the most difference.

The Holiday Doctor flow for a cold sore: complete the online form (about five minutes), our doctor reviews it the same day within consultation hours (9am to 7pm Monday to Friday, 12pm to 6pm Saturday and Sunday), often with a short call or email to confirm a clinical detail. If a prescription is appropriate, it is issued through REMPe and collectable at any Spanish pharmacy. You are only charged if a prescription is issued.

What to do for the rest of the trip

Whether you treat with pharmacy products alone or with prescription antivirals, the practical advice for the next week is the same.

• Don't touch it. If you do, wash your hands immediately — particularly before touching your eyes or any cut on your skin.
• Don't kiss anyone, especially infants or anyone immunocompromised. Cold sores are most contagious during the blister and weeping phase.
• Don't share lip products, drinks, cutlery, or razors until the sore is fully healed.
• Protect the lip from sun with a high-SPF lip product. UV is one of the strongest triggers, and a holiday is the most UV exposure many people get all year.
• Stay hydrated and get rest. Cold sores reactivate when the immune system is under pressure.
• If you have started an oral antiviral, finish the full course even if the cold sore looks better after a day or two. Stopping early reduces the benefit.
• Watch for signs of secondary bacterial infection — increasing pain, yellow crusting, swelling, or fever — and seek in-person care if any appear.

Important. The Holiday Doctor does not assess cold sores affecting the eye, widespread herpetic infections, or any of the situations listed above. If there is any possibility your situation is an emergency, call 112.