Gabapentin Dosage Calculator

Gabapentin is a prescription medicine used for several conditions, including certain forms of neuropathic pain and epilepsy. Dosing is not determined by one universal formula. Age, indication, response, adverse effects, kidney function, formulation, other medicines, and local prescribing guidance all matter. This calculator is therefore an educational arithmetic aid rather than a prescription. It shows how a proposed daily target can be converted into a renal-adjusted daily amount and divided across administrations. For a patient younger than 18, the target field is treated as milligrams per kilogram per day. The calculator multiplies that target by body weight in kilograms. For an adult, the same field is treated as a fixed total in milligrams per day. If no target is supplied, the tool uses a conservative illustrative target based on age and indication. These defaults are useful for demonstrating the math, but they are not individualized recommendations and should never replace product labeling or a clinician's judgment. Gabapentin is eliminated primarily by the kidneys, so reduced renal function can substantially increase exposure. This tool applies a simple tiered educational adjustment: the full computed target at an eGFR of at least 60, one half from 30 through 59, one quarter from 15 through 29, and one eighth below 15 mL/min. Real prescribing tables may specify dose ranges and frequencies rather than a single multiplier. Dialysis, acute kidney injury, changing renal function, and the difference between eGFR and creatinine clearance require professional interpretation. After renal adjustment, the daily amount is capped at 3,600 mg and divided by the selected frequency. The displayed per-dose amount is rounded to the nearest milligram, although available capsule, tablet, and liquid strengths determine what can actually be administered. Clinicians commonly titrate gradually to balance symptom control with dizziness, sleepiness, coordination problems, swelling, or other adverse effects. Do not start, stop, or change gabapentin based on this result. Abrupt discontinuation can cause withdrawal symptoms and may increase seizure risk. Seek urgent medical help for severe sedation, breathing difficulty, swelling, or other concerning symptoms. Always have a qualified prescriber or pharmacist review the complete clinical situation and provide the final dose and taper schedule.