What is gabapentin?

Drug class of gabapentin


Antiepileptic
Finished products (selection)

Neurontin ®
Gabax ®
Gabapentin Hexal ®

Effect

The antiepileptic drug gabapentin is a structural analogue of GABA, its exact mechanism is still unknown. It is approved for monotherapy or adjunctive therapy of partial seizures with and without secondary generalization and for the treatment of peripheral neuropathic pain.

Mechanism of action

The mechanisms of Antepileptika can be divided into three main categories:
- Suppression of repeated, prolonged neuronal discharges by maintaining the inactive state of voltage-activated sodium channels.
- Increase of gamma-aminobutyric acid (GABA)-dependent, synaptic inhibition.
- Suppression of voltage-dependent activation of a specific Ca2 + channel.
Gabapentin is an antiepileptic drug with structural resemblance to the inhibitory neurotransmitter GABA.
According to current knowledge, probably an imbalance between excitatory and inhibitory neurotransmitters in the pathogenesis of epilepsy is involved. As a result, a pathological central nervous impulse generation at the same time insufficient stimulus suppression is possible.
The mechanism of action of gabapentin is different from that of other drugs that interact with the GABAergic neurotransmission in the interaction.
Although it was developed as a GABA analogue that, unlike GABA, can penetrate the blood-brain barrier, it has no direct GABA mimetic properties in terms of effects on the inhibitory synapses. It has no affinity for GABA receptors or benzodiazepine receptors.
Recent findings suggest that gabapentin causes an increase in GABA synthesis, the mechanism of this effect is not known.
Furthermore, an effect of gabapentin on central serotonin metabolisms are discussed.
Previously also known that gabapentin affects the concentrations of excitatory amino acids by changing the transport from the extracellular space into the nerve cells and also alters their metabolism in the neurons of the CNS.
Specific binding sites for gabapentin in the neocortex were detected in the basal ganglia, hippocampus and the cortex of the cerebellum. The exact mechanism is not known.
Clinical studies show when added to standard treatment with gabapentin therapy is a significant seizure reduction in otherwise treatment-resistant patients with focal and secondarily generalized tonic-clonic (grand mal) seizures.
Gabapentin is not effective in primary generalized seizures (eg, staring), and may make the condition of patients with Lennox-Gastaut syndrome even worse.
The potential advantage of gabapentin is its supposedly lower toxicity compared with other antiepileptic drugs. For the treatment of children and adolescents, it seems therefore to be particularly suitable. Even so far been no effect of gabapentin on cognitive abilities observed and it does not seem to interact with concomitant medication.

Contraindications (contraindications)

The following are absolute Gegenanzeiegn (situations in which the drug should be administered in any case) and relative contraindications (situations in which the drug should be administered with caution) listed. For more information or answers to your questions please use the forum or ask your doctor or pharmacist.

Absolute contraindications
- Hypersensitivity to gabapentin
- Acute pancreatitis

Relative contraindications
- Gabapentin is not effective against primary generalized seizures such as Absences, it may even worsen this type of seizure.
- Pregnancy
- Breast-feeding

Side effects (adverse reactions)

This is a complete list of the known side effects, for more information or answers to your questions please use the forum or ask your doctor or pharmacist.

Adverse effects, without specifying the frequency
- Under treatment with gabapentin cases were reported of acute pancreatitis. The causal relationship with gabapentin is unclear.
- Was Suicidal ideation and suicidal behavior in patients treated with antiepileptic agents in several indications.
- Respiratory tract infections, otitis media, convulsions and bronchitis were reported only in clinical trials in children. It was also reported in clinical studies in children, aggressive behavior and hyperkinesis.


Very common adverse reactions (> 1 / 10)
- Virus Infections
- Drowsiness, dizziness, ataxia
- Fatigue, fever

Common adverse reactions (> 1 / 100)
- Pneumonia, respiratory infections, urinary tract infections, other infections, otitis media
- Leukopenia
- Anorexia, increased appetite
- Hostility, confusion and emotional lability, depression, anxiety, nervousness, abnormal thinking
- Convulsions, hyperkinesia, dysarthria, amnesia, tremor, insomnia, headache, paresthesia, such as Paresthesia, hypesthesia, incoordination, nystagmus, strengthened, weakened or absent reflexes
- Blurred vision e.g. Amblyopia, diplopia
- Dizziness
- Hypertension, vasodilation
- Dyspnea, bronchitis, pharyngitis, cough, rhinitis
- Vomiting, nausea, dental abnormalities, gingivitis, diarrhea, abdominal pain, dyspepsia, constipation, dryness of mouth or throat, flatulence
- Face edema, purpura, bruising usually described as due to a physical trauma, skin rash, pruritus, acne
- Arthralgia, myalgia, back pain, muscle twitching
- Incontinence
- Impotence, anorgasmia in women
- Peripheral or generalized edema, abnormal gait, asthenia, pain, discomfort, flu symptoms
- Decreased white blood cell count, weight gain
- Accidental injuries, fractures, abrasions

Rare adverse reactions (> 1 / 10000)
- Thrombocytopenia
- Allergic reactions (for example, urticaria)
- Hallucinations
- Movement disorders (eg choreoathetosis, dyskinesia, dystonia)
- Tinnitus
- Palpitations
- Pancreatitis
- Hepatitis, Jaundice
- Stevens-Johnson syndrome, angioedema, erythema multiforme, alopecia
- Acute renal failure
- Fluctuation in blood sugar levels in diabetics, elevated values ​​in liver function tests
- Withdrawal symptoms (mostly anxiety, insomnia, nausea, pain, sweating), chest pain. Sudden deaths with unknown cause were reported, a causal relationship to treatment with gabapentin was not identified.