Almost everyone who comes to us with a blocked, aching face asks the same question: is this a sinus infection, or just a cold that won't go away?
It's a fair question, and the honest answer is that on day three nobody can tell you. Sinusitis nearly always begins as a cold. The two share the same blocked nose, the same thick mucus, the same heavy head. What separates them is time, and which direction things are heading.
This guide explains how pharmacists actually make the call, why green mucus is less informative than people think, and when a sinus problem needs more than paracetamol and patience. Qrystal Pharmacy is at 301 Borough High Street, a couple of minutes from Borough station.
Why they're so easy to confuse
Your sinuses are small air-filled spaces behind your cheekbones, forehead and the bridge of your nose. They drain into the nose through narrow channels.
A cold inflames the lining of the nose, and that inflammation almost always spreads into the sinuses as well. Studies using scans have found sinus changes in most people with an ordinary cold. So in a sense, every cold involves the sinuses a little.
What we call acute sinusitis is when that inflammation doesn't settle as the cold passes. The drainage channels stay swollen, mucus builds up, and the pressure and pain become the main event rather than a side effect.
Most of the time this is still viral. A smaller number of cases become bacterial, and those are the ones where treatment can make a real difference.
The 10-day rule
This is the single most useful thing to know, and it's the same threshold the NHS pathway uses.
- Under 10 days: almost certainly a cold, or the early viral phase of sinusitis. Either way, self-care is the right approach and antibiotics won't help.
- 10 days or more with little improvement: now sinusitis is the likely explanation, and it's worth being assessed.
- More than about four weeks, or keeps coming back: this is outside the acute pattern and needs a GP review.
A typical cold peaks around days two or three and is clearly improving by the end of the first week, even if a cough or a stuffy nose lingers. The key word is improving. If you're at day 11 and you feel much the same as you did on day four, that's the pattern that points to sinusitis.
Symptoms that point towards sinusitis
To be assessed for sinusitis, you need at least one of:
- A blocked or congested nose, or
- Nasal discharge, including mucus running down the back of your throat
plus at least one of:
- Pain, pressure or tenderness around your cheeks, eyes or forehead, or a headache
- A reduced or lost sense of smell (in adults)
- A cough, day or night (more typical in children)
Other clues people often notice: pain that gets worse when you bend forward, an ache in the upper teeth, bad breath, and a headache that's worst first thing in the morning after mucus has pooled overnight.
A cold, by contrast, tends to lead with a sore or scratchy throat and sneezing, and facial pain is mild or absent.
What about green mucus?
This is the myth we correct most often. Yellow or green mucus is not a reliable sign of a bacterial infection. The colour comes from white blood cells doing their job, and it's common in plain viral colds.
On its own, the colour tells us very little. What matters is the overall picture. The NHS pathway looks for two or more of these features before considering a bacterial cause:
- Getting worse again after starting to get better. Sometimes called "double sickening": you were recovering from the cold, then it turned and you feel worse than before.
- A fever above 38°C
- Thick, discoloured discharge that doesn't let up
- Severe pain on one side of the face, particularly over the teeth or jaw
One of these alone usually isn't enough. Two or more together, after 10 days, is when antibiotics start to earn their place.
Could it be something else?
A few conditions produce similar symptoms and are worth ruling out.
- Hay fever and allergic rhinitis. Itchy eyes, lots of sneezing and clear, watery discharge suggest allergy rather than infection, especially if symptoms come and go with seasons or triggers. Allergies can also make sinusitis more likely, which is why the two often travel together.
- Dental problems. Pain in the upper back teeth can come from the sinuses, but it can also come from the teeth themselves. If the pain is in one tooth, is set off by hot or cold, or there's no nasal congestion, see a dentist.
- Tension headaches or migraine. Many "sinus headaches" turn out to be migraine, especially if there's no blocked nose or discharge.
This is part of why the consultation involves questions rather than a quick look. The right treatment depends on getting the cause right.
When it's urgent
Sinusitis is uncomfortable and usually harmless. Very rarely, infection spreads to the area around the eye or inside the skull, and that needs treating quickly.
Get same-day medical help (your GP, NHS 111, or 999 if severe) if you have:
- Swelling, redness or pain around one eye
- Double vision, blurred vision or any change in your sight, or an eye that looks pushed forward
- A severe headache, particularly across the forehead, or swelling over the forehead
- A stiff neck, confusion, drowsiness or sensitivity to light
- Feeling severely unwell with a high temperature
Don't wait for a pharmacy consultation if any of these apply. Our guide to urgent care near Borough sets out where to go.
What actually helps: the first 10 days
For most people, sinus symptoms settle within two to three weeks with nothing more than self-care. That's frustrating to hear when your face aches, but the evidence is consistent: antibiotics taken early in a mostly viral illness make little difference to how quickly you recover, and they carry side effects and a cost to antibiotic resistance.
What does help:
- Paracetamol or ibuprofen for pain and fever, at the correct dose
- Rest and fluids. Not glamorous, but they work
- Saline nasal sprays or rinses to loosen mucus and clear the nose
- Steam from a bowl of hot water or a shower can ease the stuffiness (not for young children, because of the scalding risk)
- Sleeping with your head raised to help drainage overnight
A word on decongestant sprays. Over-the-counter decongestant nasal sprays can bring quick relief, but use them for no more than about a week. Longer than that and the nose can become dependent, rebounding into worse congestion when you stop. Decongestant tablets aren't suitable for everyone, including people with high blood pressure or on certain medicines, so ask us before buying.
What a pharmacist can do after 10 days
Under Pharmacy First, we can assess sinusitis for:
- Adults and children aged 12 and over
- Registered with an NHS GP in England
- With symptoms that have lasted 10 days or more with little improvement
The consultation takes place in our private room and usually takes ten to fifteen minutes. After checking for red flags and asking about your symptoms, medicines and allergies, there are three possible outcomes:
- A high-dose steroid nasal spray for 14 days. For most people who have had symptoms beyond 10 days without strong signs of a bacterial infection, this is the first-line treatment. It reduces the swelling that blocks the sinuses from draining. This is a prescription-strength dose, higher than what's sold on the shelf, and we'll show you how to use it properly, because technique makes a real difference.
- Antibiotics, if two or more of the bacterial features above are present, or if a steroid spray isn't suitable or you've already tried one for two weeks without improvement. The usual choice is a five-day course of penicillin, with an alternative if you're allergic.
- Referral, if you're under 12, pregnant and the options don't suit, have symptoms beyond about four weeks, keep getting sinusitis, or have any red-flag features.
Whatever the outcome, you'll leave with a clear plan and know exactly what to do if things change. Full details are on our sinusitis treatment page.
If it keeps coming back
Three or more episodes a year, or symptoms that never fully clear, suggest something more than bad luck. Common contributors include:
- Untreated hay fever or allergies keeping the nose inflamed
- Nasal polyps or a structural issue inside the nose
- Smoking, which damages the lining's ability to clear mucus
- Dental problems in the upper jaw
Repeated short courses of treatment won't fix any of these. A GP can look for the underlying cause and, if needed, refer you to an ear, nose and throat specialist. The NHS overview of sinusitis covers the longer-term options.
Sinus season in SE1
Sinusitis follows colds, and colds follow people. From October onwards, the crowds through London Bridge station, the Northern line platforms at Borough, and the open-plan offices around Tooley Street and More London do an efficient job of passing viruses around. By mid-autumn we see a steady stream of people who are, in their words, "on day 12 of a cold."
If a sore throat is also part of the picture, our guide on when a sore throat needs antibiotics works through the same question for the throat. For the wider seasonal picture, including flu vaccination, see our winter health guide for SE1. And if the autumn term has also brought sores home from school, our guide to impetigo in children covers treatment and the school rules. For younger children, colds more often settle in the ear than the sinuses; our guide to child earache covers what to do first.
Getting seen near London Bridge
We're a short walk from most of Borough, London Bridge and Bankside:
- Borough Underground (Northern line): about 2 minutes' walk
- London Bridge (Northern & Jubilee lines, National Rail): about 8 minutes
- Guy's Hospital, Borough Market and Southwark Cathedral: all within about ten minutes
- Buses: frequent routes stop directly outside
Qrystal Pharmacy, 301 Borough High Street, London SE1 1JH. Open Monday to Friday 9:00–18:30 and Saturday 9:00–14:00.
- Call: 020 7403 2237 if you'd like to check anything first
- Walk in: no appointment needed for Pharmacy First
- Book a consultation if you'd rather hold a slot
Most sinus problems are a cold that outstayed its welcome, and time and self-care will see them off. But if you're past day 10, not improving, or getting worse after getting better, come in. That's exactly what the service is for.
