What to Do at the First Signs of a Cold

A scratchy throat in the evening, a heavy head, the first sneeze. The instinct is to find something that stops it, and there is nothing to stop: a cold is a viral infection that clears on its own, usually in about a week. What you can do is make those days easier, not pass it on, and know the signs that mean this is no longer an ordinary cold.

When to see a doctor

Most colds never need one. The exceptions, by urgency:

Right away, by emergency number — 911 in the US and Canada, 999 in the UK, 112 across the EU, 112 or 103 in Russia. In an adult: trouble breathing; persistent chest or abdominal pain or pressure; lasting dizziness, confusion, or being impossible to wake; seizures; no urine; severe muscle pain or weakness; a fever or cough that improved and then came back or worsened; a flaring chronic condition. In a child: fast or labored breathing with the ribs pulling in; blue lips or face; chest pain; muscle pain bad enough to refuse walking; dehydration — no urine for eight hours, dry mouth, no tears; not alert or not waking normally; seizures; a fever above 40 °C that will not come down; any fever in a baby under twelve weeks; getting worse after getting better. The NHS (UK) adds a stiff neck, a rash that does not fade under a pressed glass, pain in bright light, a first febrile seizure, cold hands and feet, pale or bluish skin, a child hard to rouse or extremely agitated. Neither list is complete: if what you see frightens you, call.

The same day, a doctor or phone advice line: fever lasting more than four days (CDC, US) or more than three (NHS, UK); symptoms past ten days without improvement; severe facial pain or headache; signs of dehydration. In a child, also 38 °C under three months (NHS, UK), 39 °C between three and six months, fever for five days or longer, a rash together with a fever, refusing food and drink, dry diapers, sunken eyes.

At an ordinary appointment: a cough lasting more than three weeks; sinus infections that keep returning; a chronic illness or weak immune system — worth a plan for the season.

What is happening

More than 200 respiratory viruses cause colds, rhinoviruses most often — which is why there is no vaccine against "a cold". CDC (US) puts the usual course at under a week, the NHS (UK) at improvement within one to two weeks; in small children it runs longer. A cough outlasts the rest: up to three weeks happens, longer is worth checking. Cold, flu and COVID look alike at the start, and for someone in a risk group that difference matters early.

What to do

Rest for how you feel, not to shorten the illness. No evidence says that resting at the first sign turns a week-long cold into a one-day one. It helps you through the days and keeps the virus from traveling.
Drink enough not to get dehydrated, not more than usual: "drink plenty" has no trials behind it, and too much may do harm in lower respiratory infections.
Paracetamol or ibuprofen by the label, for discomfort — not to push a number down. No aspirin under 16 (NHS, UK; under 18 in the US). For a child: no alternating or combining the two without a doctor's word; no paracetamol under two months, no ibuprofen under three months or under 5 kg, none with chickenpox or dehydration, and with asthma only on medical advice; no undressing, sponging or wrapping up, and fever medicine does not prevent febrile seizures. In pregnancy, NSAIDs including ibuprofen are not for use from week 20 without a doctor's direction (FDA, US) — paracetamol is the choice.
Honey helps a cough and never goes to a baby under one. Over-the-counter cough and cold medicines are not recommended under six (CDC, US; NHS, UK); elsewhere read the package.
Rinse the nose only with safe water: distilled, sterile, or boiled three to five minutes and cooled — never from the tap.
Skip the antibiotics: they do nothing to a virus and carry risks of their own.
Go back out (CDC guidance, US) after at least 24 hours with no fever and no fever medicine, symptoms improving — then five more days of care: mask, fresh air, distance. School and workplace rules differ by country.

When this is not the case

Some people should call early rather than wait the same symptoms out: adults 65 and older, children under five and especially under two, pregnant women, and anyone with chronic lung disease including asthma, heart disease, diabetes, chronic kidney disease, a weakened immune system, a disability with other conditions, or a BMI of 40 or more. Rarely a bacterial infection such as pneumonia follows the viral one — then antibiotics are exactly right.

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Sources

Checked: September 6, 2026