Swollen Tonsil on One Side

The tonsils are small lymph nodes situated right at the back of the throat. You can usually see them when you open your mouth wide and if they are inflamed, you will most definitely spot them, usually two swollen mounds at either side of the throat.

Occasionally, you might find that you only have swelling on one side of the throat – a swollen tonsil on one side only. Although this could be a sign of tonsillitis (which normally affects both sides rather than just one side), it could also be a sign of a couple of other conditions which will normally require some form of medical attention in order to treat them.

What Can Cause a Swollen Tonsil on One Side? 

Swollen Tonsil on One SideWe’ve already mentioned tonsillitis – one of the most common conditions which would cause swollen tonsils. When they become infected, they become very swollen and inflamed and this is when tonsillitis occurs, a condition that is very common in young children between the ages of 2 and 15 years of age.

Usually caused by a virus, or a bacteria called Streptococcus (or strep), it is often accompanied with a number of other symptoms including a very sore and red throat, bad react (halitosis), swelling of the neck, a weak voice, trouble breathing and swallowing, aches and pains, a fever and a decreased appetite.

The Streptococcus bacteria can also cause ‘strep-throat’, which carries the same symptoms as tonsillitis but can be passed on through coughing and sneezing.

If you think you have tonsillitis, a throat swab will confirm the diagnosis and then the condition can be treated with antibiotics. If the problem persists (especially in young children), the doctor may refer you for a tonsillectomy at which point the tonsils are removed and the problem should go away. In some rare cases, not all the tonsils are removed and they can grow back.

With both strep-throat and tonsillitis, the bacteria and viruses are spread through human-to-human contact so things like coughing, sneezing, touching, etc. The bacteria that causes tonsillitis can be active for a couple of weeks, and a viral infection is likely to be contagious for a slightly reduced length of time – seven to ten days.

Quinsy’ or Peritonsillar abscess as it is more formally known, is another reason why you might have a swollen tonsil on one side. This is a complication of tonsillitis and is a ball of pus collecting between the tonsil and the throat wall. An abscess forms, normally quite quickly, and it can spread the infection around the mouth and also around the body, especially if it ruptures or is not treated.

Treatment of quinsy normally involves a rather unpleasant combination of a very large needle and antibiotics. A doctor will drain the ball of pus in an attempt to get it all out but it can come back. With recurrent cases, a tonsillectomy is advised.

Quinsy will have very much the same kind of symptoms as strep throat and tonsillitis – a fever, aches and pains, headaches, sore throat, loss of appetite, etc. but can also come with a few more serious ones including difficult in breathing, a very high temperature, great difficulty and pain when trying to breathe or swallow, and a generally rather unwell feeling.

What Can Be Used to Treat a Swollen Tonsil on One Side? 

The treatment of your swollen tonsil or tonsils will very much depend on the condition. In some cases, it’s as simple as antibiotics but in others, the treatment could go as far as surgery.

There are some at-home remedies you can try if you have a sore throat, swollen tonsils, or any of the other associated symptoms. Throat lozenges can be sucked which provide relief and there are some types which offer anesthetic properties to alleviate the pain even further. You can also buy throat-sprays which help to soothe the pain and treat the bacteria or virus too.

To give your voice a break for a while, you should try to avoid too much talking and definitely no shouting and if you can, try to rest as much as you can and reduce your stress levels. Smooth foods are easier to swallow and it is important to try and eat and drink as best you can. Your immune system won’t work effectively at fighting off the bugs if it isn’t in tip-top condition itself and to achieve that, you need to make sure you have nourished it.

When to Seek Medical Advice 

Although common, a swollen tonsil on one side is something you will want to get checked out by a doctor. This is even more so the case if you have accompanying symptoms such as a high temperature, a rash over the body, no improvement after a couple of days of treatment, very dark-colored urine, difficult breathing or swollen and painful joints.

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  1. I am a 35 year old male. I have had a swollen tonsil for longer than I can remember. More than 8 years. All of my doctors stated if it is not bothering you then don’t bother getting them taken out. As of August I recently stopped smoking and using all nicotine products and started to withdraw pretty hard. I visited an ENT due to my past nicotine use. My ENT told me that he is concerned that I might have lymphoma due to the size of my tonsil and lymph node in my neck. He also stated that he would like to observe and have a follow up with me 3 months later. Hell three months later has come and past and now I am getting a biopsy of my lymph node to rule out lymphoma and other cancers. I am just wondering if one swollen tonsil is a sign of cancer wouldn’t the doctors have been more concerned and wouldn’t it have spread and continue to grow over the years?

    • It would be unwise for me to state whether or not they could have known whether or not it was cancerous. It is likely that all of your doctors believe that it was only your tonsil. You can speak with your previous doctors if you want to. Best of luck with your current situation. You have our best wishes. Have a great day, Gary!

  2. Well, I’m a 46yrs young female. I’ve had one swollen tonsil for SIX YEARS with absolutely NO symptoms. I discovered it one day by feeling a slight “thing” in my throat so I took a flashlight and saw it. At that time it looked like a clean shiney piece of skin stretched into more of a ball shape. My throat doctor ruled out any of the above with tests. He has stated on both my visits…”if it’s not getting bigger or bothering you in any way….we’ll just leave it alone.” Now it’s elongated almost like it’s starting to mirror the Palatopharyngeal arch. My urine test results came back with a high number of squamous epithelial cells but it’s common for lab results to have been contaminated. But – it does make me wonder if it’s something more serious but taking years to fully develop into something life threatening.

    • If your doctor has ruled out other causes, then follow his advice and just watch the swollen tonsil. There are risks to surgeries as well, so there is no need to put your body through those risks if there isn’t anything majorly wrong. I would continue to pay attention to your tonsils to make sure they do not become bigger–you may even want to take a picture or two to make sure that you can easily see any size changes over a few months.