Are your body's reactions too fast? Let's talk about Hyperreflexia!

Have you ever seen a doctor gently tap your knee with a small rubber mallet? Your leg will then automatically jerk, right? This is normal. But sometimes this jerk, or this reaction (reflex), happens too quickly and strongly. That's what we call Hyperreflexia in medicine. Even though this name may sound like a serious illness, there's nothing to be afraid of. Today, we'll talk about this simply, in a way that you can understand.

Let's first see, what is this reflex?

Simply put, a reflex is something that happens automatically, without our control. These are automatic mechanisms that our bodies have to protect us. Think about it, when something like an insect flies towards your eye, your eyes close automatically, right? It's not something you do consciously. It's something the body does to protect itself from potential damage. The same reflex is why we quickly pull our hand back when we touch something hot. These are essential for our survival.

So, Hyperreflexia is when those automatic reactions happen too much, or too strongly. It's normal for your leg to jerk a little when you tap your knee with a hammer. But if your leg jerks faster than you'd expect, like it's about to be thrown forward, that could be Hyperreflexia.

Why does this happen? What are the causes of hyperreflexia?

There are several reasons for this. Some are related to the nervous system, some are not.

Nervous system problems (Upper Motor Neuron Lesions)

The main and most common cause of this is damage to the nerve cells (motor neurons) that carry messages from our brain to the spinal cord. In medical terms, this is called an Upper Motor Neuron (UMN) lesion . To be precise, our brain is the main center that controls the body's movements and reactions. The messages coming from this brain go to the muscles through the spinal cord. When there is damage or obstruction somewhere along the path that carries these messages, the control of reactions becomes disrupted. Then the reactions become too strong.

The following medical conditions can cause this type of UMN damage and hyperreflexia.

Other causes not related to the nervous system

• Anxiety Disorders: If you have anxiety or panic disorder, your body is in a state of 'fight-or-flight'. This can cause your muscles and reflexes to become overly sensitive. This can also lead to hyperreflexia. However, it is not permanent and comes and goes. It is more common when you are feeling anxious or stressed.
• Hyperthyroidism: When the thyroid gland in our neck becomes overactive, the body produces an excess of thyroid hormone. This hormone speeds up the activity of every cell in our body, including nerve cells. This also speeds up reactions. With proper treatment, the condition of Hyperreflexia disappears completely.

How do you find this, Doctor?

A doctor will test you for hyperreflexia as part of a neurological exam. This is the test we all know where they tap your knee with a small rubber mallet. This is called a Deep Tendon Reflex (DTR) examination .

It is very important that you remain as calm and relaxed as possible during this test. If you are thinking about it or tensing up, the results may be wrong. That is why the doctor will sometimes talk to you about something else before doing this, to distract you.

In addition to the knee, the doctor may test reflexes in several other places.

• Back of the elbow
• Inside the crook of the hand
• Wrist and ankle

Are Hyperreflexia and Autonomic Hyperreflexia two different things?

Yes. Although these two names are somewhat similar, these two situations are completely different . It is very important to understand this difference precisely.

Autonomic Hyperreflexia (also known as Autonomic Dysreflexia) is a very serious, potentially life-threatening medical emergency. It is most commonly seen in patients with upper spinal cord injuries (above the T6 thoracic vertebra). It is an overreaction of the autonomic nervous system that causes a sudden and severe increase in blood pressure. The main symptom is a sudden, severe headache. This is a condition that requires a trip to the Emergency Department (ETU).

But the hyperreflexia we're talking about in this article is just an accelerated reaction in the joints. It's a symptom of a disease, not something that's life-threatening at that moment.

What are the treatments for this?

Treatment depends entirely on the underlying condition that caused it. The goal is to treat that root cause.

• In incurable neurological conditions like MS and ALS, treatment is used to manage the disease. Although hyperreflexia is permanent, some medications or physiotherapy can reduce the severity of the symptoms.
• Conditions like Hyperthyroidism and Anxiety can be completely controlled with medication. When the condition is treated, the Hyperreflexia symptom will also disappear.

When should I see a doctor?

It can be difficult to know if you have hyperreflexia on your own. It is usually diagnosed when a doctor examines you.

However, if you have the following symptoms, definitely see your family doctor.

• If you feel weakness in your muscles.
• If you feel stiffness (spasticity) in your limbs.
• If the limbs shake uncontrollably (clonus).
• If you feel anxious and stressed out over even the smallest things, this could be due to Anxiety or Hyperthyroidism.

Your doctor will perform the necessary tests, determine the cause, and, if necessary, refer you to a neurologist.

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