Before discussing Somatosensory System and Phenytoin, it’s critical to understand these terms. While you may already be aware, here we have explained these terms separately and in detail for those who don’t.

Key Takeaways:

1. What is Phenytoin?
2. Epilepsy and its causes
3. Seizures and symptoms
4. Somatosensory System and Phenytoin

Phenytoin

Phenytoin (a prescription medicine), is an anticonvulsant drug used to treat seizures and often associated with epilepsy. Anticonvulsant drugs can also be used to treat bipolar disorder, migraines, and nerve pain. Seizures occur when the normal communication between brain cells is disrupted. This can happen due to various factors, such as a high fever, low blood sugar, high blood sugar levels, sudden withdrawal from alcohol or drugs, or a head injury. Phenytoin prevents, controls, and treats seizures, during or after the surgery to the brain. This drug comes under different brand names, including but not limited to Dilantin, and Phenytek. It is important to note that this drug can have serious interactions with alcohol.

Epilepsy:

Two or more unprovoked (not caused by anything) seizures that occur more than 24 hours apart are considered epilepsy. It’s a neurological condition that can have many causes, including genetic factors, brain damage, infections, and metabolic issues. It is important to note that in about half of cases, the cause of epilepsy is unknown, and approx. 2.2 million Americans are living with this chronic noncommunicable (non-transferrable) disease. The above-given factors have been described as follows;

Genetic factors

• A genetic tendency passed down from a parent
• A new genetic change in the person
• Genetic conditions like tuberous sclerosis or neurofibromatosis

Brain damage

• Brain damage from a stroke, head injury, or lack of oxygen at birth
• Brain damage from infections like meningitis, encephalitis, or neurocysticercosis
• Brain damage from brain tumors

Metabolic issues

• Metabolic problems like GLUT-1 deficiency syndrome, which affects glucose transport to the brain
• Vitamin and mineral deficiencies

Other causes

• Developmental brain abnormalities
• Drug abuse or alcohol misuse
• Hormonal changes, like those that occur during menstruation
• Sleep issues, like sleep apnea
• Physical and emotional stress

Triggers

• Flashing lights or patterns
• Certain foods, like caffeine
• Dehydration
• Missing doses of anti-seizure medication

What are Seizures?

A seizure is essentially a sudden, uncontrolled burst of electrical activity in the brain. This disruption in normal brainwave patterns can lead to a variety of symptoms, including:

1. Uncontrolled Muscle Movements

• Types: These can range from subtle twitching to violent jerking of limbs.
• Tonic-clonic seizures: Characterized by a stiffening phase (tonic) followed by a phase of rhythmic jerking (clonic).
• Myoclonic seizures: Brief, shock-like jerks of muscles.
• Focal seizures: May involve localized muscle twitching or jerking in a specific part of the body.

2. Changes in Sensation

• Sensory symptoms can precede, accompany, or follow a seizure.
• Tingling or numbness: Often described as a pins-and-needles sensation.
• Burning or prickling: A hot or cold sensation.
• Strange tastes or smells: Hallucinatory sensations.
• Visual disturbances: Flashing lights, blurred vision, or tunnel vision.

3. Loss of Consciousness

• Can range from brief lapses of awareness to prolonged unconsciousness.
• Absence seizures: Brief periods of “spacing out” or staring into space.
• Tonic-clonic seizures: Often involve a loss of consciousness during the seizure.
• Post-ictal state: A period of confusion or drowsiness that can follow a seizure.

4. Psychological Symptoms

• Fear and anxiety: Can occur before, during, or after a seizure.
• Confusion and disorientation: May occur after a seizure, especially if the person has experienced a loss of consciousness.
• Déjà vu: A feeling of having already experienced a situation.
• Jamais vu: A feeling of unfamiliarity with a previously familiar situation.

Somatosensory System Role

The Somatosensory System is a network of neurons that allows people to perceive touch, pressure, temperature, pain, and movement. It’s also known as the somatic sense or tactile perception. It plays a crucial role in seizure activity in several ways:

Sensory Triggers: In some cases, sensory stimuli can trigger seizures. For example, flashing lights or loud noises can induce seizures in individuals with photosensitive epilepsy.
Somatosensory Cortex Involvement: The somatosensory cortex, located in the parietal lobe of the brain, plays a critical role in processing sensory information. Seizures originating in this area can manifest as unusual sensations, such as tingling, numbness, or a burning sensation.
Aura: Some individuals with epilepsy experience an aura before a seizure. Auras are often sensory experiences, such as unusual smells, tastes, or feelings of déjà vu. These sensory phenomena provide valuable insights into the location of the seizure focus in the brain.

Somatosensory System and Phenytoin

Phenytoin is an anti-seizure medication that may also be used to treat irregular heartbeats in some cases It works by stabilizing the electrical activity of neurons. It can affect the somatosensory system in several ways:

• Direct effects on sensory nerves: Phenytoin can interact with the nerves responsible for transmitting sensory information, potentially leading to altered sensations like numbness, tingling, or a loss of feeling.
• Effects on brain regions involved in sensory processing: Phenytoin can influence the activity of brain regions involved in processing sensory information, such as the somatosensory cortex. This can result in changes in sensory perception and interpretation.
• Interactions with neurotransmitters: Phenytoin can affect the levels or activity of neurotransmitters involved in sensory processing, which can also impact sensory perception

Phenytoin Side Effects: Phenytoin can cause a range of side effects, including:

Neurological: Dizziness, drowsiness, headache, tremor, nystagmus (rapid eye movements), ataxia (loss of coordination), slurred speech, confusion, and in severe cases, seizures or coma.

Other: Swollen gums, fatigue, nausea, vomiting, and increased hair growth.

Long-term use of high doses of phenytoin can lead to decreased bone density due to interference with vitamin D metabolism, increasing the risk of fractures.

• Phenytoin Therapeutic Effects: By stabilizing neuronal activity, phenytoin can help reduce the frequency and severity of seizures, including those with somatosensory symptoms.

Important:

CYP2C9 and CYP 2C19, belonging to the P450 family are primarily responsible for metabolizing phenytoin. Since Pharmacogenomics testing shows what type of metabolizer you are to certain drugs, it’s possible to know how your body shall respond to Phenytoin.

What is Pharmacogenomic Testing and How Does it Work?

This is a noninvasive test requiring only saliva, which is collected with a simple cheek swab. It shows how your body may respond to 250+ medications, minimizing trial and error while allowing your doctor to tailor medicines according to your genetic makeup.

Conclusion

Seizures and epilepsy have complex challenges, but advancements in understanding the somatosensory system and medications like phenytoin have improved treatment outcomes. Phenytoin’s ability to stabilize neuronal activity makes it a cornerstone in seizure management, though careful monitoring is essential to mitigate side effects – personalized medicine approaches, such as pharmacogenomics testing, are paving the way for individualized treatments, involving fewer or no trials and more efficacy.

References:

https://www.hopkinsmedicine.org/health/conditions-and-diseases/epilepsy#:~:text=Epilepsy%20is%20a%20neurological%20condition,million%20Americans%20live%20with%20epilepsy.
https://my.clevelandclinic.org/health/drugs/20270-phenytoin-capsules

 

Disclaimer: This blog is only for informational purposes. Please always consult a doctor before taking any medical action.