Gabapentin

Gabapentin is a drug from the group of anticonvulsants, which belongs to the category of antiepileptic drugs similar in structure to GABA, which acts as an inhibitory neurotransmitter of the central nervous system.

Its chemical structure is similar to GABA, which functions as an inhibitory transmitter in the central nervous system. Scientists believe that the mechanism of action of gabapentin is different from that demonstrated by other anticonvulsants that act through the GABA synapse (including valproate, barbiturates, benzodiazepines, GABA transaminase inhibitors, GABA uptake inhibitors, GABA agonists, and GABA prodrugs). As of 2024, a number of animal studies indicate that gabapentin is distinguished by the presence of a new peptide binding site in brain tissue, including the hippocampus and cerebral cortex. This may explain the anticonvulsant activity of gabapentin and its derivatives. At clinically relevant concentrations, gabapentin does not bind to other conventional drugs and neurotransmitter receptors in the brain.

What Is Gabapentin Used for

The list of indications for the use of gabapentin is quite wide. First of all, the indications for taking this medicine include the occurrence of partial days with and without secondary generalization in adults and children over 12 years of age. Also, as an additional component, gabapentin is recommended for the treatment of partial seizures with and without secondary generalization in adults and children aged 3 years and older. Another common indication for gabapentin is the treatment of neuropathic pain in adults. In particular, gabapentin has proven effective in the treatment of herpes zoster, namely a complication such as postherpetic neuralgia. [1]

Postherpetic neuralgia is a serious painful sensation that occurs along the path of a nerve infected with the herpes virus. Sometimes, even years after infection, it literally does not allow the patient to lead a full life, to the point that patients independently take strong painkillers, including injectable ones. In this case, gabapentin may be the very life-saving remedy that helps you return to normal life. However, it does not begin to act quickly in the case of treatment of postherpetic neuralgia, and sometimes it takes 2-3 months before a noticeable effect occurs. Inflammation of the facial nerve is another indication for the use of gabapentin. However, since the pain associated with facial neuralgia is one of the most severe and requires high dosages of medication, there is a fairly high risk of developing severe side effects. This is due to the fact that, in general, gabapentin is recommended to be taken incrementally. Some doctors recommend using gabapentin to relieve cluster headaches or migraines (during exacerbations).

The medicine may be prescribed for leg cramps and a condition known as restless legs syndrome. Sometimes it is also used to relieve pain from osteochondrosis and arthritis, as well as trigeminal neuralgia.

Gabapentin Side Effects

The list of side effects of gabapentin is quite long. From the nervous system, conditions such as amnesia, ataxia, confusion, impaired coordination of movements, depression, dizziness, dysarthria, increased nervous excitability, nystagmus (involuntary movements of the eyeballs), drowsiness, thinking disorders, tremor, convulsions, amblyopia, diplopia, hyperkinesia, increased, weakened or absent reflexes, paresthesia, anxiety, hostility, gait disturbance.

From the digestive system, changes in tooth staining, diarrhea, increased or lost appetite, dry mouth, nausea, vomiting, flatulence, anorexia, gingivitis, abdominal pain, pancreatitis, and changes in liver function tests may be observed.

On the part of the hematopoietic system, there are cases of leukopenia, a decrease in the number of leukocytes, and thrombocytopenic purpura.

From the respiratory system, rhinitis, pharyngitis, causeless cough, and pneumonia can develop.

From the musculoskeletal system, patients note myalgia (often), arthralgia.

From the cardiovascular system, the body can react with arterial hypertension and manifestations of vasodilation.

From the urinary system, urinary tract infections and urinary incontinence are possible.

Allergic reactions can manifest as erythema multiforme and Stevens-Johnson syndrome.

Dermatological reactions include skin maceration, acne, itching, rash.

Other negative side effects include back pain, fatigue, peripheral edema, decreased libido, impotence, anorgasmia, asthenia, malaise, facial swelling, weight gain, flu-like syndrome, fluctuations in blood glucose, in children – viral infection, otitis media. [2]

Gabapentin Dosage

The gabapentin dosage regimen is individual and is prescribed by a doctor depending on the individual patient, indications and treatment regimen. In general, it is preferable to reach an effective dosage not immediately, but gradually, giving the body the opportunity to adapt to the medicine. The drug is prescribed orally regardless of food intake. If it is necessary to reduce the dose, discontinue the drug, or change it to an alternative agent, this should be done gradually over a period of at least one week to ensure that the patient does not experience withdrawal symptoms.

Epilepsy usually requires long-term treatment. The dose of the drug is determined by the attending physician depending on individual tolerability and effectiveness of the drug.

Gabapentin 300mg

For neuropathic pain in adults, the initial dose is 900 mg/day in three equal doses. If necessary, depending on the effect, the dose is gradually increased to a maximum of 3600 mg/day. It must be taken into account that when using the drug at a dose above 1800 mg/day, additional effectiveness is not observed. For adults and children over 12 years of age with epilepsy, the effective dose is from 900 to 3600 mg/day. Therapy can be started with a dose of 300 mg 3 times a day on the first day or increased gradually to 900 mg. In this regard, 300 mg of gabapentin is the most widely used and convenient dosage. It is this version of the drug that accounts for the overwhelming majority of sales of this drug.

Gabapentin 100mg

Gabapentin 100 mg is used primarily in children between the ages of 3 and 5 years. The effective dose of gabapentin in children aged 5 years and older is 25-35 mg/kg body weight/day in equal doses in 3 doses. The effective dose of gabapentin in children aged 3 to 5 years is 40 mg/kg body weight/day in equal doses in 3 doses. The drug was well tolerated in doses of up to 50 mg/kg body weight/day with long-term use.

Is Gabapentin Generic for Lyrica

Quite often, patients wonder if gabapentin is a generic drug called Lyrica. This is due to the fact that Lyrica’s active ingredient is pregabalin, which many people confuse with gabapentin. Although Lyrica and gabapentin can be used as antiepileptic drugs and to treat nerve pain, there are significant differences between them.

Gabapentin is a separate drug that is not a generic version of pregabalin, nor is pregabalin a generic version of gabapentin. However, they both belong to the same class of drugs known as gabapentinoids. Their actions are a little similar to each other. Despite this, both drugs are not interchangeable. If a patient is prescribed Lyrica, switching to gabapentin may not be helpful or even harmful, and vice versa. In addition, Lyrica is not used to treat restless leg syndrome or pain caused by shingles.

Side effects from taking Lyrica are more common than from taking gabapentin. This is especially true for weight gain, constipation and swelling. Lyrica begins to act faster and is eliminated from the body also faster. From the point of view of addictiveness, Lyrica is a more dangerous drug, and it must be taken under strict medical supervision. [3]

Generic Gabapentin 100mg

Generic gabapentin attracts patients primarily due to its lower cost. This is especially true for those patients who need long-term treatment – in particular, with epilepsy and treatment of postherpetic neuralgia. In addition, gabapentin 100 mg in generic form is in demand due to the fact that generic manufacturers, the vast majority of which in the pharmaceutical market by 2024 are large Indian companies, pay increased attention to purification of the active substance. This leads to a reduction in the severity of side effects.

Generic Gabapentin 100 mg can be purchased online under brand names such as Gabasign, Gabatop, Gabapentin Sandoz, Gabimax and others.

References

[1] Kukkar, Ankesh, et al. “Implications and mechanism of action of gabapentin in neuropathic pain.” Archives of pharmacal research 36 (2013): 237-251.

[2] Quintero, Gabriel C. “Review about gabapentin misuse, interactions, contraindications and side effects.” Journal of experimental pharmacology (2017): 13-21.

[3] Carter, Gregory T., et al. “Side effects of commonly prescribed analgesic medications.” Physical Medicine and Rehabilitation Clinics 25.2 (2014): 457-470.