What is Gabapentin?

Gabapentin is one of number of anti seizure medications (Anti-epileptic). It is used off licence to treat Fibromyalgia and unlike Pregabalin is is not approved by the FDA in the USA for the treatment of Fibromyalgia. It is often prescribed to treat Neropathic pain in patients with Diabeties or Shingles. Gabapentin extended-release tablets (Horizant) are used to treat restless legs syndrome ( A condition that causes discomfort in the legs and a strong urge to move the legs, especially at night and when sitting or lying down and is a symptom of Fibromyalgia)

Other names

Neurontin®, Gabarone


I am unsure on the exact dosages however trials were conducted with a daily dose of between 1,200mg and 2,400mg .

How it Works

The mechanism of action of gabapentin is not known. Gabapentin structurally resembles the neurotransmitter gamma aminobutyric acid (GABA)

These anti epileptic drugs are used to reduce the level of pain signals sent due to excess neuron firing as part if the central nervous system. Neuronal activity in the brain can be modified by the presence of excitatory or inhibitory neurotransmitters, which exist in balance in the nervous system. The ratio of these chemicals determines how likely it is that a neuron will fire. Two major excitatory neurotransmitters are amino acids: glutamate and aspartate. Two main inhibitory neurotransmitters are glycine, another amino acid, and GABA (gamma aminobutyric acid), a derivative of glutamate. The excitatory chemicals increase the charge of neurons, while inhibitory ones make the neurons more negatively charged (less likely to fire). When neurons fire, they release other neurotransmitters like serotonin and dopamine. This means that the decrease in serotonin levels often seen in Fibromyalgia patients could possibly be a result of altered GABA function. The excitatory/inhibitory neurotransmitter balance acts as a master regulator of the sensitivity of the nervous system.

Side Effects

Gabapentin may cause side effects like drowsiness, tiredness or weakness, dizziness, headache, uncontrollable shaking of a part of your body, double or blurred vision, unsteadiness, anxiety, memory problems, strange or unusual thoughts, unwanted eye movements, nausea, vomiting, heartburn, loose stools, dry mouth, constipation, increased appetite, weight gain, swelling of the hands, feet, ankles, or lower legs, back or joint pain, fever, runny nose, sneezing, cough, sore throat, or flu-like symptoms, ear pain, red, itchy eyes (sometimes with swelling or discharge). Although this is a comprehensive list it does not mean the drug has more or less side effects than others or that they are more common. Any drug has side effects and your Doctor can help you manage them during your treatment however some side effects may be serious. If you experience any rash, itching, swelling of the face, throat, tongue, lips, or eyes, hoarseness, difficulty swallowing or breathing or seizures then call your doctor immediately.

Gabapentin on netdoctor.co.uk
Gabapentin on patient.co.uk

This page will contain information on medications used in the treatment of Fibromyalgia and some of my personal experiences using them. This page is for information only. It is not medical advice and everyone considering taking any medication should discuss the matter with their doctor first. If you have been prescribed any of these drugs, make sure you read the documentation with them, as this section is not meant to be a substitute for this important process.