How gabapentin works
Gabapentin is a drug with anticonvulsant (antiepileptic), analgesic (analgesic), and sedative properties. It belongs to the group of antiepileptic drugs.
The human nervous system is activated or inhibited by certain neurotransmitters. Normally, these neurotransmitters are released according to external circumstances and ensure an appropriate response of the body to various situations such as injury, stress or rest.
Long-term irritation of the nerve pathways in the back and limbs (peripheral neuropathy) due to severe diabetes or viral diseases of the nervous system (e.g., herpes viruses) also lead to overexcitability of the nerve endings. As a result, they constantly send signals of irritation to the brain, and the patient feels constant pain. This so-called nerve pain (neuralgia) cannot be treated with normal painkillers.
On the one hand, the drug prevents the release of activating messenger substances. On the other hand, it indirectly promotes the breakdown of activating messenger substances and thus additionally lowers their concentration in the nervous system. Fewer messenger substances then bind to their receptors – tension and pain states are relieved.
However, the full effect of the drug unfolds only after a certain period of intake (about one to two weeks).
Absorption, degradation and excretion
The active substance is excreted unchanged via the kidney. Therefore, the dose must be reduced in people with renal impairment.
When is gabapentin used?
The indications for use (indications) of gabapentin are:
- Peripheral neuropathic pain, e.g. as a result of diabetes (diabetic polyneuropathy) or herpes infection (postherpetic neuralgia)
How gabapentin is used
Gabapentin is usually used in the form of tablets or capsules. The drug can be taken with or without food, but always with enough liquid (preferably a large glass of water).
At the beginning of therapy, gabapentin is dosed gradually. This means that the dosage is started low and gradually increased until a sufficient daily dose is reached. This so-called “titration” can take several weeks, depending on individual tolerance. Titration is important because the doctor has to find a dose that is specifically tailored to the patient and that provides sufficient efficacy and as few side effects as possible.
In the case of neuropathic pain, a discontinuation attempt can be tried after a certain treatment period. However, not abruptly, but by gradually reducing the dose over at least one week (“tapering”).
What are the side effects of gabapentin?
Respiratory disorders, nausea and vomiting, muscle pain, impotence and skin rashes are also possible. Less than one percent of those treated experience water retention in the body tissues (edema).
What should be considered when taking gabapentin?
Drug interactions
If morphine (strong analgesic) is taken at the same time, the concentration of gabapentin in the blood may increase. Therefore, the dose of gabapentin may need to be reduced for the duration of morphine therapy.
Age Limitation
Gabapentin is approved in combination with other medications (add-on therapy) for focal seizures with and without secondary generalization from the age of six years. Approval for monotherapy is for patients twelve years of age and older.
Pregnancy and lactation
Experience with more than 500 pregnancies using gabapentin in the 1st trimester does not indicate an increased risk of malformation. However, since such a risk cannot be completely ruled out, a strict risk-benefit assessment is always appropriate before using the drug.
To date, no side effects have been reported in breastfed infants when the mother is taking gabapentin. Therefore, use of the drug during breastfeeding is acceptable, although the infant should be monitored closely.
How to obtain medication with gabapentin
What else you should know about gabapentin
Due to lower effectiveness, gabapentin is not a first-choice antiepileptic drug, but is considered a so-called reserve drug. However, it may be useful to combine other antiepileptic drugs with gabapentin.