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Tonsillitis and strep throat checker Portugal
Answer a few questions about your sore throat to see how likely a bacterial cause is, and what the usual next step would be. It takes about a minute.
- Uses the published McIsaac score, age-adjusted — not a score we invented
- Flags the warning signs that need urgent care before it scores anything
- Runs in your browser — nothing is sent or stored
Your symptoms
years
A temperature over 38 °C, or feeling feverish and shivery, at any point since it started.
A cough points towards a virus, so the score counts its absence rather than its presence.
Just under the jaw on either side, sore when you press them — not the glands at the back of the neck.
Look with a torch at the back of the throat. This is hard to judge on yourself and is the weakest answer in the score.
Also drooling, a muffled voice, severe pain on one side only, or a stiff or swollen neck.
Often a fine, rough, sandpaper-like rash on the chest or neck.
Including chemotherapy, carbimazole, methotrexate or long-term steroids. A sore throat can be the first sign of a problem with your white blood cells.
1points
Bacterial infection unlikely
This pattern is still much more often viral than bacterial. Self-care is usually right, but this is not a negative test — see a doctor if the pain worsens, a fever climbs, or you are no better after a week.
- Symptoms matched
- 1 / 4
- Age adjustment
- 0
This estimates how likely a sore throat is to be bacterial. It is not a strep test and not a diagnosis — only a throat swab or an examination can confirm one. A low score means a bacterial infection is unlikely, not that it has been ruled out. Never start or stop antibiotics based on this page.
01
What your score means
The score runs from -1 to 5. Four features each add a point — a fever, no cough, tender glands at the front of the neck, and white patches on the tonsils — and age adjusts the total up or down. Children aged 3 to 14 gain a point; adults over 45 lose one, because strep throat becomes uncommon with age.
The bands below describe how likely a bacterial cause is, not how bad the sore throat feels. A viral sore throat can hurt a great deal and still score zero.
0 or below
- Bacterial cause
- Very unlikely
- What it usually means
- Self-care. Rest, fluids and pain relief; see a doctor if it is no better after a week.
1
- Bacterial cause
- Unlikely
- What it usually means
- Usually self-care, with a review if it worsens rather than settles.
2
- Bacterial cause
- Possible
- What it usually means
- The point at which a doctor would normally want to look at your throat rather than guess.
3
- Bacterial cause
- More likely
- What it usually means
- Guidelines prompt an examination and often a swab. Arrange a consultation.
4 or 5
- Bacterial cause
- Most likely
- What it usually means
- The group most likely to be tested and to be considered for antibiotics. Arrange to be seen.
02
The five things the score asks about
Each one is there because it shifts the odds between a virus and a bacterial infection, and together they do better than any single symptom on its own.
- Fever — bacterial throat infections are more likely than viral ones to come with a temperature over 38 °C.
- No cough — a cough points strongly towards a virus, so the score counts its absence. This is the criterion people most often get backwards.
- Tender, swollen glands at the front of the neck — the lymph nodes that drain the tonsils, which swell and hurt when the tonsils are infected.
- White patches or swelling on the tonsils — pus on the tonsils raises the odds of a bacterial cause, although a virus can produce it too.
- Age — strep throat peaks between 5 and 15 and becomes uncommon after 45, so the score adds a point for children and subtracts one for older adults.
03
What this checker cannot tell you
A score sorts likelihoods. It does not identify what is growing in your throat, and it was designed for a clinician who is looking at one.
- It is not a strep test. Only a throat swab or a rapid antigen test can confirm a bacterial cause, and a doctor takes it.
- A low score is not a negative result. It means a bacterial cause is unlikely on the balance of odds, not that it has been ruled out.
- Two of the answers are examination findings. A clinician feels the glands and looks at the tonsils with a light; judging those on yourself is the least reliable part of this page.
- It does not decide anything about antibiotics. That is a prescribing decision a doctor makes after examining you, weighing your history and often a swab result.
- It says nothing about glandular fever, which can look identical at first and is common in teenagers and young adults whose sore throat drags on.
- It does not apply to children under 3, where it is not reliable and a doctor should assess instead.
04
When a sore throat needs urgent care
These override the score completely. A serious throat infection can start out looking mild and score low, so none of the following should ever be weighed against a reassuring number.
- Difficulty breathing, noisy breathing, or a sense that the throat is closing — get emergency help immediately.
- Unable to swallow your own saliva, or drooling.
- Unable to open the mouth fully, or severe pain on one side with a muffled voice — this can be an abscess beside the tonsil.
- A stiff neck, or swelling in the neck that is getting worse.
- A fine, sandpaper-like rash alongside the sore throat — scarlet fever needs treating.
- A sore throat while on chemotherapy, carbimazole, methotrexate or long-term steroids — this needs same-day assessment and a blood count.
- A sore throat that is still getting worse after a week, or a fever you cannot bring down.
Where to go from here
A sore throat that scores high is a reason to be examined, not a diagnosis. These are the consultations that can take it further.
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Sore throat checker: FAQs
Is this the same as a strep test?
No. A strep test is a swab of the throat, either sent to a laboratory or run as a rapid antigen test in the clinic. This page estimates how likely a bacterial cause is from your symptoms, which is what a clinician uses to decide whether that swab is worth taking. It cannot replace the swab.
What is the difference between tonsillitis and strep throat?
Tonsillitis describes inflamed tonsils, whatever the cause — most often a virus. Strep throat is tonsillitis or pharyngitis caused by one particular bacterium, Streptococcus pyogenes, known as group A strep. Every case of strep throat is tonsillitis; most tonsillitis is not strep throat.
Do I need antibiotics for a sore throat?
That is a decision for a doctor, not for this page. Most sore throats are viral, where antibiotics do nothing and still carry side effects. A high score means the odds of a bacterial cause are high enough that a doctor would usually examine you and consider testing — it does not mean antibiotics are indicated.
How long should a sore throat last?
Most settle within about a week, whether viral or bacterial. A sore throat that is still worsening after a week, or that comes with a fever you cannot bring down, is worth having looked at regardless of what this checker says.
Why does the score subtract a point if I am over 45?
Because strep throat becomes uncommon with age. The original Centor score was built for adults and over-called bacterial infection in older patients; McIsaac's age adjustment corrects for that in both directions, adding a point for children aged 3 to 14, where strep is most common.
Does this checker store my answers?
No. The scoring runs entirely in your browser. Nothing you select is sent to our servers or saved.
Do I need a prescription for antibiotics in Portugal?
Yes. Antibiotics are prescription-only in Portugal, so a pharmacy cannot dispense them for a sore throat without one. A pharmacist can advise on pain relief and tell you whether they think you should be seen, but the prescribing decision belongs to a doctor who has examined you.
Where can I get a sore throat examined in Portugal?
A family doctor can look at your throat and take a swab if the pattern warrants it. Emergency services are for the warning signs listed above, not for ordinary tonsillitis. Our registered doctors can review your symptoms by video consultation and advise whether a swab or an in-person examination is the right next step.
Need someone to look at your throat?
Book a video consultation with a registered doctor, go through your symptoms, and find out whether a swab, a prescription or simple self-care is the right next step.