What to Know About Areflexia

Medically Reviewed by Dan Brennan, MD on October 25, 2021
3 min read

Damage to any nerve in your body can have unexpected results. In some cases, damage to a nerve can cause you to lose a muscle reflex, like the one that makes your knee jerk during a physical exam. When this happens, it’s called areflexia.

Areflexia is one symptom of nerve problems. You may also get other muscle problems along with the loss of involuntary reflexes. If you’re having muscle weakness or losing muscle mass, your doctor may test your reflexes and discover areflexia.

If you have it, your doctor will figure out how much nerve damage you have and explain what treatments could help.

Areflexia means the absence of deep tendon reflexes. Tendons are the tight cords of tissue that connect muscles to bones. Typically, when you tap on a tendon, it causes the muscle to contract and move involuntarily. You’ve probably seen this happen at a checkup, when a doctor tapped the side of your knee and your leg jumped automatically. Other tendons cause similar responses in different parts of your body, including the arm, elbow, ankle, and belly.

If your doctor taps on a tendon and there isn’t a reflexive movement in the muscle, it’s a sign of a health issue. Usually, absent reflexes are caused by an issue with the nerves in the tendon and muscle. You may have other muscle symptoms along with areflexia, like weakness, twitching, or atrophy.

It’s generally a symptom of peripheral neuropathy, which is damage to a nerve in the peripheral nervous system. This system includes nerves outside the brain and spinal column.

If you have neuropathy, you may notice other symptoms as well as changes to your reflexes, such as:

Nerve damage can have a lot of causes, including illnesses and injuries. Some of the reasons for areflexia include:

Diabetes. High blood sugar can damage nerves, especially in your legs and feet. This can also cause slowed or absent reflexes. Controlling your blood surge can lower your chances of getting more nerve damage.

Autoimmune disorders. Ones like lupus, rheumatoid arthritis, and amyotrophic lateral sclerosis (ALS) can cause damage to nerves.

Organ system conditions. Illnesses that affect your internal organs can cause nerve problems over time. Kidney disease, liver disease, connective tissue disorders, and an underactive thyroid may lead to neuropathy.

Infection. Some viral or bacterial infections can result in neuropathy that affects reflexes. Lyme disease, shingles, Epstein-Barr virus, hepatitis B and C, and HIV have all been linked to neuropathy.

Medications. Sometimes the prescription medicines for severe illnesses have harmful side effects, including nerve damage. Some types of chemotherapy for cancer list neuropathy as a possible side effect.

Tumors. Any type of growth, whether it’s cancerous or not, has the potential to affect the nerves around it. The pressure from the tumor can press the nerve and cause damage.

Talk to your doctor if you have any symptoms of neuropathy. If it turns out that you have nerve damage, they can find out the cause. And the sooner they do, the better their chances of successfully treating the condition.

Treatment for areflexia and neuropathy depends on what’s causing the nerve damage. Sometimes it’s related to a treatable condition. In that case, you may be able to improve your symptoms by getting help for the underlying issue.

In other cases, the damage may be permanent. Your doctor can help you manage the symptoms, though. Medications may help with any pain. Physical therapy may help you strengthen muscles affected by damaged nerves.

Some causes of neuropathy are outside of your control. Injuries, tumors, and autoimmune disorders can affect anyone. Some types of neuropathy are tied to lifestyle choices that lead to conditions like liver disease or type 2 diabetes. Eating a healthy diet and getting regular exercise can lower your risk for health issues that might damage your nerves.

If you have any signs of neuropathy or areflexia, see your doctor. They’ll figure out what’s going on and show you how to manage your symptoms.