Why does skin hurt when touched? (+1 reasons)

In this article, we will discuss why your skin can become sensitive to touch. This sensitivity can cause pain, even when there are no visible indications of bruising, rashes or other skin disorders.

Why does skin hurt when touched?

Your skin can hurt when touched due to problems with the nervous system and nerve endings. This condition is known as allodynia. It is a type of neuropathic pain which is characterised by unexpected discomfort from non-painful stimuli, such as slight touching, cold temperatures, wearing a t-shirt or combing your hair.

Pain is a natural way of your body telling you to stop doing whatever is causing discomfort to your sensory nerves. The pain you experience due to allodynia can range from mild to severe. Some patients feel a burning sensation, while others might feel a minor ache. Nonetheless, it can still cause discomfort. 

How does touching cause skin pain?

The researchers believe that mechanical pain is signalled by afferent mechanoreceptors present in the skin. These mechanoreceptors are coupled with extensive myelinated axons that typically encode the nonpainful tactile stimuli. As a result, patients suffering from skin pain are likely to have central sensitization as the underlying mechanism (1).

Central sensitization, causing skin pain while touching, is characterized by an increase in neuron excitability in the spinal cord and thalamus. These alterations can cause a lower activation threshold, greater activation, or the induction of new inputs.

Hence, central sensitization can cause greater sensitivity in the wounded area as well as enhanced pain in the uninjured area. This could potentially explain the clinical phenomena of hyperpathia. In hyperpathia, the patient experiences more than the usual pain (2).

What are different stimuli that can cause pain while touching?

Various stimuli can cause skin pain, which other normal circumstances do not elicit any pain response. These stimuli can include:

• Dynamic or mechanical stimuli: patients with this condition experience pain when their skin comes in contact with clothing or bedding.
• Thermal stimuli: this pain may be explained by the increased excitability of temperature-sensitive nociceptors. It can be triggered by a drop of cold or warm water on the skin.
• Static stimuli: It is characterized by the interaction of sensory modalities that are physically and functionally isolated. It can be triggered by gentle tapping or hand-holding. 

What does research suggest?

In one of the clinical studies, 53.3% of the patients (n=295) with migraine reported allodynia. A correlation existed between the duration of illness, frequency of migraine attacks, and allodynia. The age of the patient had little impact on the occurrence of allodynia (3). 

Another interesting finding suggested that the administration of high doses of morphine can increase the occurrence of hyperalgesia and allodynia. The clinical manifestation of allodynia reversed when morphine was discontinued (4).

In another clinical study, 57.5% of the patients (n=993) suffering from irreversible pulpitis reported mechanical allodynia. The mechanical allodynia was lined to early phases of odontogenic pain due to inflammation of vital pulpal tissues (5).

Which diseases increase skin pain due to touching?

Various diseases can increase the pain threshold while touching, including (6):

• Postherpetic neuralgia: it occurs due to shingles. It is characterized by burning, stabbing, soreness, and tingling sensation due to touch.
• Trigeminal neuralgia: it is caused by injury to the trigeminal nerve. It involves severe and sudden facial pain 
• Postamputation pain: limb amputation can cause nerve damage that can cause aching, throbbing and scorching pain.
• Painful nerve lesions and injuries: these are characterized by muscular weakness, cramping, and uncontrollable muscular twitching due to nerve damage.
• Fibromyalgia: it is a chronic disorder in which the patient experiences musculoskeletal pain accompanied by insomnia and fatigue.
• Diabetes: increased blood sugar can eventually lead to diabetic neuropathy. It is characterized by nerve damage that can decrease the pain threshold.
• Migraine: skin sensitivity and pain are more common in patients with chronic migraine. Allodynia increases the occurrence and intensity of headaches.
• Female hormones: Female reproductive hormones reduce the strength of the pain stimulus required to induce pain and make the skin more sensitive.
• Injury and trauma: injury to the nerves due to amputation, accident, surgery, and stroke can increase the likelihood of pain sensitivity.
• Obesity and smoking: these two factors increase the chances of skin pain because they reduce the pain threshold.
• Medicines: certain medicines, like opioids and chemotherapeutic agents, can increase skin sensitivity to pain. 

How to relieve skin pain and sensitivity while touching?

The clinical intervention to pain while touching is often decided according to the underlying disease. Some of the common interventions might include:

• Nerve blocks: they are an effective method of preventing, and reducing pain sensation by interfering with pain signalling throughout the body, especially to the brain.
• Pain relievers: oral and topical formulations are often used to treat the pain. Topical medication can include lidocaine and capsaicin. 
• Antimigraine agents: Triptans can relieve the pain sensitivity associated with migraines.
• Anticonvulsant drugs: Pregabalin (Lyrica) is often prescribed for fibromyalgia. It also acts as an analgesic and anxiolytic agent.
• Physical therapy: this includes desensitization procedures where the physiotherapist gradually increases the pressure with time until the pain becomes bearable.

Being a diabetic, I began to feel unusual pain in my hands, feet and legs. I had never experienced such pains in the past or suffered any injuries recently. When I visited my doctor, I was diagnosed with diabetic neuropathy.

As a word of advice, you should never ignore signs that occur out of the blue. Always consult your doctor about the occurrence of these symptoms and discuss possible clinical interventions. 

References