Most upper respiratory infections (URIs) are caused by viruses, and antibiotics don’t work on viruses. That means there’s no “best antibiotic” for a typical URI: no antibiotic will cure it or help you get better faster. Doctors prescribe antibiotics only when they find a bacterial infection, such as strep throat, some sinus infections or bacterial pneumonia.
Get care right away for trouble breathing, chest pain, noisy breathing (wheezing or a high-pitched sound), confusion, or skin between the ribs pulling in with each breath. Cleveland Clinic lists these, along with a high fever and dizziness, as reasons to go to the emergency room with a URI. If you think it’s an emergency, call 911.
In the video above, family physician Dr. Mason Jones explains that the cause of a URI, the vast majority of the time, is a virus, and that the common cold doesn’t respond to an antibiotic at all. He says even a powerful broad-spectrum antibiotic, which he calls “the big gun,” probably won’t change your symptoms. And he warns that giving antibiotics to everyone with a cold would wipe out many of the helpful bacteria we normally carry, including those in the digestive tract. For URI symptoms, home care and prevention, see the full write-up on the video page. This article focuses on one question: when do antibiotics help?
What does acute URI mean?
URI stands for upper respiratory infection: an infection in the upper part of the respiratory system, which includes the nose, sinuses and throat, Cleveland Clinic explains. “Acute” simply means sudden. MedlinePlus says acute symptoms appear, change or get worse quickly, and it’s the opposite of chronic. So “acute URI” on a visit summary usually means a sudden infection of the nose and throat, most often a common cold.
Do you need antibiotics for an upper respiratory infection?
Usually not. Cleveland Clinic says most URIs are viral, caused by germs such as common cold viruses, flu viruses, the virus that causes COVID-19, and RSV. MedlinePlus says plainly that antibiotics should not be used to treat a common cold.
The American Academy of Pediatrics (AAP) says antibiotics for colds, flu, RSV and COVID-19 won’t help you feel better or keep others from getting sick. The NHS adds that antibiotics don’t work for most coughs, and are no longer routinely used for chest infections, ear infections in children, or sore throats.
Green or yellow mucus doesn’t change this. MedlinePlus says a runny nose often thickens and turns yellow or green within a few days of a cold, which is normal. The AAP and MedlinePlus both say colored mucus alone doesn’t mean a bacterial infection.
When do doctors prescribe antibiotics for a respiratory infection?
Some respiratory infections are caused by bacteria. Cleveland Clinic names strep throat and some cases of sinusitis as bacterial URIs. Here are the main situations, and the signs that point to bacteria, according to the sources we read.
| Infection | Usually viral or bacterial? | Signs that suggest bacteria or a need for antibiotics |
|---|---|---|
| Common cold | Viral | None; antibiotics don’t help |
| Flu, COVID-19, RSV | Viral | None; antibiotics don’t help |
| Sore throat | Usually viral | A positive rapid strep test or throat culture |
| Sinus infection | Usually viral | Symptoms that don’t improve after about 10 days, or that get better and then worse |
| Ear infection | Many clear on their own | A doctor decides; the NHS says most clear within 3 days |
| Pneumonia | Viral, bacterial or fungal | A doctor’s exam and tests; antibiotics treat the bacterial kind |
Strep throat
Strep throat is caused by group A Streptococcus bacteria. MedlinePlus says antibiotics are given only if a strep test is positive, and that penicillin or amoxicillin is usually tried first. A sore throat with a cough and runny nose points to a virus, the AAP says, so testing usually isn’t needed then. More: Is Strep Throat Viral or Bacterial?
Sinus infections
MedlinePlus says acute sinusitis can be caused by viruses or bacteria, and that most of these infections go away on their own. Even when antibiotics help, they may only slightly shorten the illness. Signs that point to bacterial sinusitis include:
- in adults, symptoms after a cold that don’t improve, or get worse, after 7 to 10 days (MedlinePlus)
- a runny nose, stuffy nose and facial pain that don’t go away after ten days (Cleveland Clinic)
- symptoms that improve and then come back worse (Cleveland Clinic)
- in children, a high fever with dark nasal discharge for at least 3 days, or nasal discharge for more than 10 days without improvement (MedlinePlus)
Cleveland Clinic says providers often wait to see how long symptoms last before prescribing antibiotics.
Ear infections
The NHS says most ear infections clear up within 3 days, though symptoms can last up to a week, and that antibiotics are no longer routinely used for ear infections in children. A doctor may still prescribe them. The NHS says to see a doctor if earache hasn’t improved after 3 days, if a baby under 12 months may have an ear infection, or if there’s swelling around the ear, fluid coming out, or a change in hearing.
Pneumonia
Pneumonia is a lung infection, not an upper respiratory infection, but MedlinePlus says a cold can lead to it. The National Heart, Lung, and Blood Institute (NHLBI) says antibiotics may be prescribed for bacterial pneumonia, antivirals are sometimes used for viral pneumonia, and antifungals treat fungal pneumonia. Symptoms include cough, fever, chills, shortness of breath, and chest pain when breathing or coughing. Older adults may have a lower-than-normal temperature instead of a fever and may seem weak or suddenly confused.
The AAP says a child whose breathing gets better and then worse again, with a new fever or new symptoms, should be checked for bacterial pneumonia or sinusitis.
Which antibiotic is best for a respiratory infection?
It depends entirely on which bacterial infection a doctor finds, and for a viral URI, the answer is none. That’s a decision for your doctor, not something to choose from a list.
For reference, the NHS says most antibiotics fall into six groups, including penicillins (such as amoxicillin), cephalosporins, macrolides (such as azithromycin), tetracyclines (such as doxycycline) and fluoroquinolones. The NHS notes that fluoroquinolones are no longer routinely used because of the risk of serious side effects. Your doctor will also ask about allergies: the NHS says allergic reactions are especially linked to penicillins and cephalosporins.
The downsides of antibiotics you don’t need
An antibiotic you don’t need can still cause harm.
- Side effects. The NHS lists feeling sick or being sick, bloating, indigestion and diarrhea as common. The AAP lists diarrhea, vomiting, stomach pain and rash, and says antibiotic side effects are a common reason children go to the emergency room.
- Allergic reactions. Some are serious. The NHS treats these signs as an emergency (call 911): a skin rash, wheezing, chest or throat tightness, trouble breathing or talking, or swelling of the mouth, face, lips, tongue or throat.
- Antibiotic resistance. MedlinePlus says resistance happens when bacteria change so they can resist an antibiotic, and that each time you take antibiotics, there’s a risk the bacteria will become resistant. Resistant infections can be hard to treat and are sometimes deadly.
MedlinePlus advises:
- Don’t use antibiotics for viruses.
- Don’t pressure your provider for an antibiotic they don’t think you need.
- Follow the directions carefully when you do take one.
- Don’t save antibiotics for later, use someone else’s prescription, or share yours.
What actually helps a URI
There’s no specific treatment for most viral URIs, Cleveland Clinic says, but fluids and over-the-counter medicines can ease symptoms. MedlinePlus recommends rest and fluids, and notes that over-the-counter cold medicines may ease symptoms in adults and older children but don’t shorten a cold, and aren’t recommended for children under 4. The AAP suggests a humidifier for congestion, and honey for cough in children over 1 year old. Ask your doctor or pharmacist which over-the-counter medicine is right for you.
When to see a doctor
See a doctor if:
- symptoms get worse, or don’t improve after 7 to 10 days (MedlinePlus)
- symptoms are severe, last longer than two weeks, or keep coming back (Cleveland Clinic)
- you get better and then worse, especially a child with a new fever or worse cough (familydoctor.org, AAP)
- you have severe sinus pain, a swollen gland in the neck or jaw, or a high fever that won’t go away (familydoctor.org)
- you have a weakened immune system or a condition that raises your risk of severe illness (Cleveland Clinic)
- a baby under 3 months has a fever above 100.4°F (AAP)
Go to the ER or call 911 for the emergency signs at the top of this article.
Frequently asked questions
What is the best antibiotic for an upper respiratory infection?
For most URIs, there isn’t one, because most are viral and antibiotics don’t work on viruses. If a doctor finds a bacterial infection, such as strep throat, they’ll choose the right medicine for that specific infection.
What does acute URI mean?
It means a sudden infection of the nose, sinuses or throat. “Acute” means sudden (MedlinePlus), and URI means upper respiratory infection. It’s most often a cold.
What are the symptoms of a URI?
Cleveland Clinic lists fever, sore throat, cough, runny or stuffy nose, sneezing, a hoarse or lost voice, tiredness, facial pain, wheezing and swollen lymph nodes. Not sure if it’s a cold or allergies? See Allergy Symptoms vs. a Cold.
How long does a URI last?
Cleveland Clinic says viral URIs usually last one to two weeks. MedlinePlus says most cold symptoms go away within a week.
Will antibiotics make my cold go away faster?
No. MedlinePlus says antibiotics shouldn’t be used for a common cold, and the AAP says they won’t help you feel better or keep others from getting sick.
Is a URI contagious?
Yes, when it’s caused by a virus or bacteria. Cleveland Clinic says viral URIs are most contagious in the first few days of symptoms, and sometimes a day or two before symptoms start.
Find a doctor: Dr. Mason Jones (family medicine, Austin), Dr. Michael Dotti (family medicine, Dallas-Fort Worth) and Dr. Robert Wyatt (ear, nose and throat, Dallas-Fort Worth).
Sources
- Cleveland Clinic. Upper Respiratory Infection (URI).
- Cleveland Clinic. Sinus Infection (Sinusitis).
- MedlinePlus (U.S. National Library of Medicine). Common cold.
- MedlinePlus (U.S. National Library of Medicine). Acute.
- MedlinePlus (U.S. National Library of Medicine). Sinusitis.
- MedlinePlus (U.S. National Library of Medicine). Strep throat.
- MedlinePlus (U.S. National Library of Medicine). Antibiotic Resistance.
- National Heart, Lung, and Blood Institute. Pneumonia: Treatment.
- National Heart, Lung, and Blood Institute. Pneumonia: Symptoms.
- American Academy of Pediatrics, HealthyChildren.org. Why Most Sore Throats, Coughs & Runny Noses Don’t Need Antibiotics.
- American Academy of Family Physicians, familydoctor.org. Colds and the Flu.
- NHS. Antibiotics.
- NHS. Ear infections.
This article is for general information only and is not medical advice. Talk with a qualified health professional about your own situation. If you think you may have a medical emergency, call 911.
