A doctor can give you a carpal tunnel injection into your wrist to help eliminate pain or numbness caused by this condition. These injections are very popular among doctors to manage a patient's symptoms. But do they work? Are they safe? You might be surprised by the facts.

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If you have carpal tunnel symptoms like hand or finger pain, numbness, tingling or weakness then you're probably a candidate for steroid injections. In fact, they're one of the most common treatments for carpal tunnel syndrome. Injections (or "shots") contain a steroid, technically called “cortisone” or “corticosteroid”. 

You may have heard of steroid pills or syrup. They're similar to these shots but in an oral form. 

The injectable form goes through a hypodermic needle and directly into the problem area. In this case, the wrist. That’s why the shots are commonly used to treat carpal tunnel syndrome. But the injections can also relieve any tender or inflamed joint, like the shoulder, knee or hip.

Usually, inflammation causes pain. The steroid injections reduce inflammation and therefore the associated pain. Inflammation causing carpal tunnel syndrome is no different. That's why a carpal tunnel injection is used to relieve inflammation in the wrist and the pain it produces. 

A carpal tunnel injection of corticosteroid is primarily used when other nonsurgical remedies did not help. Those other remedies most often include rest, wearing a wrist brace at night, myofascial release massage or taking pain relief medicines like Meloxicam, Tylenol, Advil or Motrin.

In general, a carpal tunnel injection of corticosteroid is an effective pain reliever for this condition. But the effects are not a guarantee.

• When they work, the injections usually act quickly - within hours or days. 
• And sometimes the pain relief lasts for weeks or months. 
  

So what's the problem?

In 2017, the National Institutes of Health asked carpal tunnel doctors how effective a carpal tunnel injection really was as a treatment. Its findings surprised almost everybody.

In spite of these shots being so popular, the report showed they are not as effective as most doctors believed. Quoting the National Institutes of Health. in general, a carpal tunnel injection: 

"...provided noticeable short-term relief from symptoms in about 45 out of 100 people."

That’s only 45% effectiveness.

Furthermore, any pain relief is temporary. It typically lasts for a few weeks to several months. This depends on many factors like the level of pain, length of time you had pain, and if you have other chronic illnesses like diabetes or arthritis.

The report goes on to say that this effectiveness isn’t so dramatic. That's because in 30% of patients, carpal tunnel symptoms improve on their own - without shots. 

All this brings the popular use of a carpal tunnel injection into question.

Now consider the strong recommendations of the American Academy of Orthopedic Surgeons (AAOS). They tell doctors to try all other forms of pain management before a carpal tunnel injection of corticosteroid is attempted. 

The AAOS’s warns doctors: 

1. They can administer steroid injections only 3 times a year into a single joint. 
   
   
2. If 3 shots don't help relieve pain, more shots are not likely to have an effect. 
   
   
3. The likelihood of steroid injections doing harm (see below) increases with additional shots. 
   

Therefore, doctors must limit the number of injections used to treat carpal tunnel patients.

All medications have some side effects. However, most people don't feel them. Others just cope with them because the “therapeutic effect” is much greater than the side effects. In other words, the benefits of the medicine may be more important than any side effects it produces.

Side effects for medicines are sometimes called "adverse effects" or "adverse events". There are 2 levels: "potentially dangerous" and "less dangerous".

These side effects have serious undertones and can mean a life-threatening condition. While they're rare, call 911 if they occur:

• Trouble breathing
• Swelling in your face, lips, tongue or throat

These carpal tunnel injection side effects are not as dangerous. They're also rare, and include:

• Pain and swelling around the injection site (if it lasts more than 2 days).
• Increased appetite
• Nervousness or restlessness
• Infection-like fever or a sore throat
• Persistent nausea, stomach pain or vomiting
• Bloody or black, tarry stools
• Quick weight gain
• Changes in vision like blurriness or eye pain
• Muscle pain, weakness or cramps
• Changes in skin, like reddish purple lines, rash, hives or acne
• Thirstiness, especially with frequent urination

The most common carpal tunnel injection side effect pain and swelling around the injection site. It usually lasts for 1-2 days. Any more time needs your doctor’s attention. But you can ease the pain with ice for 15 to 20 minutes every 2 hours.

Finally, there is a very rare possibility of another side effect. Any hypodermic injection into a joint or tendon has the tiny risk of piercing a tendon, ligament or nerve. These can cause joint weakness or even some paralysis.

A carpal tunnel injection of corticosteroids cannot be used under certain conditions. These are called “contraindications”. No one should have steroid shots of any kind if:

• The patient is a child.
• A woman is pregnant or breastfeeding.
• The doctor suspects an infection.
• A patient takes other medicines that steroids interfere with.
  

Always check with your doctor to ensure he or she knows about all the medicines you take. Remember to include supplements and vitamins. Only then can the doctor determine if you're a candidate for a carpal tunnel injection.

Many doctors will still administer a carpal tunnel injection of a corticosteroid drug on a regular basis. This is in spite of 1) research showing they're not as effective as popularly thought, and 2) cautions from regulators about their safety. In contrast, many non-surgical remedies provide far better outcomes in treating carpal tunnel syndrome.