Gabantin (Gabapentin 400mg) Capsules

Gabantin general information

What is Gabantin used for?

Our brain is the control centre for our whole body.  It works like an efficient machine unless there is a malfunction somewhere in the central nervous system.  Abnormal bursts of brain activity can result in conditions like epilepsy and neuropathic (nerve) pain.  Gabantin capsules 400mg are used to control seizures in epilepsy and to reduce pain sensations and relieve symptoms of neuropathic pain primarily in the arms and legs.  

Epilepsy

Epilepsy is a neurological disorder that is characterised by recurring unpredictable seizures or fits that vary in frequency and range from mild to severe.  Epilepsy covers a spectrum of seizure types, depending on where the abnormal brain activity starts, and how much of the brain is involved.  Generalised seizures affect both sides of the brain at the same time.  The most severe form is a generalised tonic-clonic seizure (previously called a grand-mal), which causes loss of awareness and uncontrollable jerking and twitching movements.  A focal seizure (previously called partial) begins in one side of the brain, and awareness can remain.  However, a focal seizure can spread to both sides and become a tonic-clonic seizure.  Causes are often unknown but may be related to a head injury, diseases like Alzheimer’s, a brain tumour, and infection like meningitis. Specific triggers have been identified, such as hormonal changes, flickering lights, high fever, and some foods.  

Nerve pain

Pain is the signal that your body is in danger of harm.  Injury and tissue damage trigger nerve endings on sensory nerves, which respond by sending messages to the brain.  These messages are interpreted as pain that is usually felt as aching and throbbing.  This type of acute pain is called nociceptive pain, caused, for example, by a cut, a burn, or a fracture.  Inflammation, which is the body’s response to injury and helps the healing process, can also cause pain, which is due to release of chemicals at the site of an injury.  Inflammation can cause long term or chronic pain if it persists for more than a few weeks. 

Nerve pain works differently and is caused by damage to or disease of the nervous system, resulting in a malfunction of the nerves sending pain signals to the brain.  Nerve pain may be triggered by an injury but persists after the injury has healed due to sensitisation of the nervous system.  The sensation of nerve pain is quite different and is described as electric shocks, stabbing, burning, extreme sensitivity to touch, also with tingling, numbness or pins and needles.  Examples of nerve pain include shingles, trigeminal neuralgia (affects the face and teeth), sciatica (compression of nerves in the spine), phantom limb pain following amputation, and diabetic neuropathy, where peripheral nerves are damaged mainly in the legs and feet.  

How does Gabantin work?

Gabantin capsules 400mg contain gabapentin, an anticonvulsant that is used to treat epilepsy and nerve pain.  Gabapentin in Gabantin capsules works by controlling certain neurotransmitters that send nerve signals from the brain.  Neurotransmitters are chemicals that allow nerve cells to communicate.  Some stimulate nerve activity, known as excitatory neurotransmitters and others dampen down nerve activity.  GABA (gamma-aminobutyric acid) is the primary inhibitory neurotransmitter.  It reduces the transmission of nerve signals from the brain to other parts of the central nervous system.  Although gabapentin in Gabantin capsules has a similar chemical structure to GABA (analogue), it does not work through the same receptors (binding sites) in the brain as GABA.  It, therefore, has a different mechanism of action to other drugs that work through the GABA receptor.  Gabapentin is thought to bind to a different receptor known as the alpha-2-delta receptor, which is a subunit of the voltage-gated calcium channels.  These are ion channels in the cell membranes of nerve cells that propagate electrical signals. 

When gabapentin binds to its receptors, it blocks the transmission of nerve signals and reduces the amount of nerve excitation that causes epileptic seizures and nerve pain, which helps control symptoms associated with epilepsy and neuropathic pain.

What does Gabantin contain?

Gabantin capsules 400mg contain the active ingredient gabapentin sodium (400mg), an anticonvulsant that is used to control epileptic seizures and nerve pain.  Gabantin also has the following inactive ingredients: Glyceryl behenate, Hydroxypropyl cellulose, Low substituted hydroxypropyl cellulose, Magnesium stearate, Mannitol, Talc, Pregelatinized starch, Opadry YS - 1-7003 ( hypromellose , titanium dioxide , polyethylene glycol & polysorbate 80)

What are the side effects of Gabantin?

Most medications have some side effects, but they are not experienced by everyone.  Some side effects are commonly experienced when taking Gabantin, but others are not so common, and you should discuss any problems or concerns with your primary care physician. 

Common side effects when taking Gabantin include dizziness or light-headedness, fatigue, drowsiness, asthenia (weakness), fever, lack of coordination (ataxia), gastrointestinal upset (constipation, diarrhoea, nausea, vomiting), weight gain, muscle pain, cramps, back pain, peripheral oedema (swelling of the hands or feet), hypertension, vasodilatation, bruising, rash, impotence, vertigo, nystagmus (involuntary eye movement), tremor, infection, confusion or abnormal thinking, visual disturbances.  

When should Gabantin not be used?

Have a talk with your primary healthcare physician before taking Gabantin capsules 400mg so that you have a full understanding of what this medicine is for and how to use it.  There are some reasons for not taking a medication; these are called contraindications, and for Gabantin you should consider the following before taking Gabantin:

• Have you ever had an unusual reaction or an allergy when taking Gabantin?
• Are you pregnant or breastfeeding?
• Do you have any problems with your kidneys?
• Do you have mixed seizure disorders that include absence seizures?

What medications interact with Gabantin?

Some medicines interact with Gabantin capsules 400mg and may affect the way it works, or are affected by Gabantin or increase side effects; you should discuss possible interactions with your primary care physician.  These may include cimetidine for peptic ulcers, antacids for reflux, opiate analgesics like morphine. 

If other medications may interact with Gabantin, your doctor will discuss these with you. 

How should Gabantin be taken and for how long?

You should take your Gabantin capsules 400mg swallowed whole with a glass of water with or without food, three times daily and do not allow more than 12 hours between doses.  The dose you take depends on what you are being treated for and your doctor’s recommendations.  Your doctor may increase your dose gradually depending on how well your condition is controlled.  You should not suddenly stop taking your Gabantin capsules 400mg as this may cause withdrawal side effects, instead, your doctor will reduce your dose gradually over one week when you are ready to discontinue treatment.  You should continue to take your Gabantin capsules 400mg for as long as recommended by your doctor even if you are feeling better, as Gabantin helps control your condition but does not cure it.

Missed dose of Gabantin

If you miss a dose of Gabantin capsules 400mg take it as soon as you remember, unless it is time to take the next dose, then skip the missed dose.  Do not take a double dose.

How should Gabantin be stored?

You should store your Gabantin capsules 400mg below 25°C in a cool dry place.