Generality
Gabapentin is an active ingredient used in the treatment of epilepsy and peripheral neuropathic pain .
Gabapentin was synthesized with the aim of creating an active ingredient capable of exerting an agonist action against gamma-aminobutyric acid receptors (GABA), one of the most important neurotransmitters inhibiting the central nervous system. The goal, therefore, was to create a drug with a GABA-mimetic action that could be useful in the treatment of epilepsy, similarly to other active ingredients with a similar action (such as barbiturates and benzodiazepines). Paradoxically, gabapentin does not show any type of GABA-mimetic activity, but its site of action is believed to be on the calcium channels . Despite this, the exact mechanism of action with which this active ingredient is able to control epileptic seizures and with which it is able to induce analgesia in the presence of peripheral neuropathic pain does not seem to have been completely clarified yet.
In order to exercise its action, gabapentin must be taken orally . In fact, the medicines that contain it are in the form of capsules or coated tablets. The dispensation of these medicines can take place upon presentation of a repeatable medical prescription (RR); however, it is a band A drug whose cost can therefore be reimbursed by the National Health System (SSN).
Curiosity
Gabapentin is also known by the female name of gabapentin .
Examples of Specialties Medications containing Gabapentin
- Keneil®
- Gabapentin Almus®
- Gabapentin DOC®
- Gabapentin EG®
- Gabapentin Mylan®
- Gabapentin Pfizer®
- Neurontin®
Therapeutic indications
When is the use of Gabapentin indicated?
The use of gabapentin is indicated in the treatment of:
- Various forms of epilepsy (both epileptic seizures limited to localized brain areas and epileptic seizures that spread to different areas of the brain).
- Peripheral neuropathic pain (for example, induced by diseases such as diabetes and herpes zoster, commonly known as shingles )
Did you know that ...
Gabapentin can be prescribed either as a support treatment (combination therapy) or other anti-epileptic therapy when it is not able to fully control seizures, or as the only treatment (monotherapy) in adults and children over 12 years of age .
Warnings
Warnings and Precautions for the use of Gabapentin
Before starting treatment with gabapentin, you should inform your doctor if:
- You are suffering from kidney disease;
- It is in hemodialysis;
- You suffer from respiratory diseases and / or pathologies of the nervous system;
- You are over 65 years of age.
In any case, as a precautionary measure, before taking medications based on gabapentin, it is advisable to inform the doctor of your health conditions, informing him of the possible presence of disorders or diseases of any kind.
Furthermore, if during treatment with gabapentin symptoms such as nausea, vomiting and persistent stomach pain appear, it is necessary to contact the doctor immediately as they could indicate the onset of acute pancreatitis.
During treatment with gabapentin it is also important to inform your doctor immediately if symptoms such as:
- Suicidal thoughts and self-harm;
- Muscle weakness;
- Soreness and pain;
- Malaise;
- Temperature;
- Urine discoloration;
- Blood test abnormalities and, in particular, increased blood levels of creatine phosphokinase.
Please note
Cases of abuse and dependence have been reported following the marketing of gabapentin-containing medicines (post-marketing experience).
Finally, remember that taking gababentin could cause side effects that can alter the ability to drive vehicles and / or use machinery (for example, drowsiness, dizziness, and tiredness). Therefore, extreme caution is advised and similar activities should be avoided should the above mentioned side effects occur.
Pharmacological Interactions
Interactions between Gabapentin and other drugs
Before taking gabapentin, it is good to tell your doctor if you are taking, or if you have recently been taken:
- Other antiepileptic drugs;
- Drugs used to treat sleep disorders;
- Antidepressant drugs;
- Anxiolytic drugs;
- Drugs used in the treatment of psychiatric disorders;
- Drugs used to treat neurological disorders;
- Opioid drugs (may increase the effect of gabapentin; in addition, the opioid-gabapentin combination can cause drowsiness and decreased respiratory rate);
- Antacid drugs containing aluminum and magnesium (may reduce the absorption of gabapentin at the gastric level, therefore, it is recommended to take gabapentin not earlier than two hours after taking the antacid drug based on aluminum and / or magnesium).
However, before starting gabapentin therapy, you need to tell your doctor if you are taking, or have recently taken, any drugs or products of any kind, including medicines without a prescription (SOP). ), OTC drugs, herbal and herbal products and homeopathic products.
Side effects
Side Effects Caused by the Intake of Gabapentin
Like any other active ingredient, gabapentin can also cause side effects, although not all patients manifest them or manifest them in the same way. In fact, each person reacts subjectively to the administration of the drug manifesting side effects that are different in type and intensity, or not manifesting them at all.
However, below are some of the major side effects that can occur during treatment with gabapentin.
Blood disorders
Treatment with gabapentin could cause leukopenia and thrombocytopenia.
Nervous system disorders
Taking gabapentin could lead to the appearance of:
- Drowsiness;
- dizziness;
- Headache;
- Ataxia;
- Dysarthria;
- Tremors;
- Hypoaesthesia;
- Disorders of coordination;
- Alterations of reflexes;
- Convulsions;
- nystagmus;
- Changes in cognitive functions.
Psychiatric disorders
Treatment with gabapentin could favor the appearance of:
- Confusional states;
- Nervousness and agitation;
- Anxiety;
- Depression;
- Emotional instability;
- Suicidal and self-defeating thoughts.
Cardiovascular disorders
Administration of gabapentin could lead to vasodilation, hypertension and palpitations.
Gastrointestinal disorders
Gababentin intake can cause:
- Nausea and / or vomiting;
- Abdominal pain;
- Dyspepsia;
- Diarrhea or constipation;
- Flatulence.
Furthermore, in rare cases, pancreatitis may occur.
Lung and airway disorders
Gabapentin therapy could promote the onset of:
- Cough;
- Dyspnoea;
- Bronchitis;
- Pharyngitis;
- Rhinitis;
- Respiratory depression.
Skin and subcutaneous tissue disorders
Treatment with gabapentin could lead to the appearance of:
- Skin eruptions;
- Acne;
- Itch:
- Stevens-Johnson syndrome;
- Erythema multiforme;
- Alopecia;
- Rash with eosinophilia and systemic symptoms.
Musculoskeletal and connective tissue disorders
Taking gabapentin may cause:
- arthralgia;
- Myalgia;
- Muscle contractions;
- myoclonus;
- Rhabdomyolysis.
Other side effects
Other side effects that could occur during treatment with gabapentin consist of:
- Allergic reactions, even serious, in sensitive individuals;
- Anorexia;
- Increased appetite;
- Hypoglycemia or hyperglycemia (side effects observed mainly in patients with diabetes);
- Infections (respiratory, ear, urinary);
- Vision disorders;
- Tinnitus;
- Dizziness;
- Dry mouth;
- Gingivitis and other dental disorders;
- Fatigue;
- Temperature;
- Peripheral or generalized edema;
- Liver and / or renal diseases and disorders;
- Impotence and sexual dysfunction.
Overdose
In the case of an overdose of gabapentin, acute toxicity may occur characterized by symptoms such as:
- Drowsiness;
- Lethargy;
- dizziness;
- Speech disorders;
- Double vision;
- Diarrhea;
- Loss of consciousness.
Treatment with excessively high doses of the active ingredient is generally symptomatic and supportive . Hemodialysis can be useful in patients with kidney problems .
In any case, in the case of an overdose of gabapentin - ascertained or presumed to be - it is advisable to go immediately to the nearest emergency room, taking care to bring along the packaging of the medicine used.
Action mechanism
How does Gabapentin work?
As mentioned, the exact mechanism of action with which gababentin is able to exert antiepileptic and analgesic activity against peripheral neuropathic pain is still not entirely clear. However, its action site is believed to be on the voltage-dependent calcium channels . More in detail, gababentin has been shown to be able to bind with high affinity to the alpha-2-delta (α-2-δ) subunit of the above mentioned channels. Therefore, it has been hypothesized that this link leads to a series of responses that could be responsible both for the anticonvulsant activity (through the reduction of the release of excitatory neurotransmitters in some areas of the brain), and the analgesic activity.
Use and Posology
How to take Gabapentin
Gabapentin must be taken orally ; in fact, it is available in the form of hard capsules and coated tablets that must be swallowed whole with plenty of water .
For the treatment of epilepsy in adults and adolescents and for the treatment of peripheral neuropathic pain in adults, the usual starting dose varies from 300 mg up to 1800 mg of gabapentin per day, to be taken in divided doses according to medical indications . After that, the amount of drug administered can be gradually increased by the doctor up to a maximum of 3600 mg of gabapentin per day.
For the treatment of epilepsy in children aged six or over, on the other hand, the average dose of gabapentin required to control seizures is 25-35 mg / kg of body weight per day.
However, the exact dosage (dose and duration of treatment) of gabapentin must be established by the doctor on an individual basis for each patient and may vary depending on the type of disorder being treated (epilepsy or peripheral neuropathic pain), and depending on the patient's response to the same treatment.
Please note
Patients with kidney disease and disorders, hemodialysis patients and elderly patients may need to reduce their usual doses.
Pregnancy and breastfeeding
Can Gabapentin be taken during pregnancy and during breastfeeding?
The risk of taking gabapentin in pregnant women is not known; however, animal studies have shown reproductive toxicity .
Furthermore, studies conducted on other antiepileptic drugs have shown the possibility of suffering changes in the development of the fetus. In particular, the combination of several antiepileptic drugs increases the risk of the development of congenital malformations (for example, cleft lip, cardiac malformations, neural tube defects).
In light of the above, therefore, the use of gabapentin in pregnant women should be avoided unless the potential benefits expected for the mother outweigh the possible risks to the fetus . In such situations, the drug could be used but only under the strict supervision of the doctor .
Women of childbearing age who need to start a gabapentin therapy, on the other hand, should use contraceptive methods in order to avoid a possible pregnancy.
As for nursing mothers, since gababentin is excreted in breast milk and the effects it might have on the baby is not known, it is advisable to avoid breastfeeding during treatment with the active ingredient in question.
Contraindications
When Gabapentin should not be used
The use of gabapentin is contraindicated in case of known hypersensitivity to gabapentin itself and / or to one or more of the excipients contained in the medicinal product to be used.
