01 Four hundred milligrams is a rung, not a once-daily habit
Four hundred milligrams is the Neurontin capsule this leaf locks. The bottle also comes as 100 and 300 mg capsules and as 600 and 800 mg tablets. Postherpetic neuralgia often starts at 300 mg on day 1, 300 mg twice on day 2, 300 mg three times on day 3, then up. Epilepsy in adults often starts at 300 mg three times daily. A 400 mg three-times-daily board is a later place on those ramps, not a first swallow from a friend's bottle.
Three times daily exists because the half-life is 5-7 hours when kidneys work. Once-daily 400 mg is a renal-step pattern, not a convenience hack for a CrCl of 90. The titration margin is the sedation file. The renal ink is the creatinine file.
Horizant and Gralise are other gabapentin products with other food rules. Do not convert them milligram-for-milligram into a 400 mg Neurontin capsule.
| Creatinine clearance | Total daily range (label) | Example 400 mg-shaped rhythm |
|---|---|---|
| >= 60 mL/min | 900-3600 mg | 400 mg three times daily sits on this row |
| 30-59 mL/min | 400-1400 mg | 400 mg twice daily is a listed BID option |
| 15-29 mL/min | 200-700 mg | 400 mg once daily is a listed QD option |
| 15 mL/min | 100-300 mg | A 400 mg capsule is already above this daily ceiling |
| Hemodialysis | Maintenance + post-dialysis supplement | Do not invent the supplement from this leaf |
02 Pain ramps and seizure ramps are not the same paper
PHN wants a 300 mg-shaped climb before a 400 mg TID board. Epilepsy often starts at 300 mg three times in adults and must come down over at least a week. Copying a pain stop onto a seizure medicine is how status gets written up.
If the 400 mg bottle arrived because 300 mg was out, ask for a written first-three-days total. Strength availability is not a titration plan.
Mood change or a spreading rash during a climb: call, do not uptitrate. Peripheral edema that changes shoes is worth a mention. DRESS is uncommon and urgent.
When creatinine falls, reread the renal ink before the next 90-count. A 400 mg TID habit on a CrCl of 25 is an overdose pattern.
03 How to keep aluminum or magnesium two hours away from a 400 mg capsule
Food is fine with Neurontin. Aluminum or magnesium antacids are not fine in the same minute. The insert wants about two hours of space. Move the capsule or move the antacid. Write both times if each is three times a day.
Opened powder plus an antacid at the same swallow is a worse version of the same problem. If swallowing is hard, ask about the oral solution. Do not mix a sweet juice 400 mg on a child's tray.
Horizant and Gralise keep their own food rules. Do not convert those products into this 400 mg rhythm just because an antacid is in the cupboard.
If you also take the fluoxetine 40 mg capsule, say both names. They are different stories. The pharmacist still needs the list. The titration margin is the climb file.
04 A chair nap on 400 mg is a titration or a kidney story
Sedation that puts you in a chair is a reason to stop climbing, not a reason to move all three capsules to 22:00. Night piles raise fall risk and make an opioid at 21:00 more dangerous.
Creatinine can move after an ACE inhibitor, a dehydrating week, or a lost ten kilograms. Sleepiness on a previously tolerated 400 mg TID is a clearance question. The renal ink reprints the rows.
Do not drop to every-other-day from a 400 mg bottle. QOD is not a printed row. Ask them to rewrite the daily total. At CrCl 15 the daily range is 100-300 mg. One 400 mg capsule already overshoots that day.
Epilepsy tapers still want at least a week. Do not stop on Friday because a drink-heavy weekend is coming. That is two CNS changes at once.
05 Sedation is why the ramp exists
Dizziness, somnolence, and ataxia show up early. That is why the PHN schedule does not start at 400 mg three times daily on a Monday. People who jump there fall, then add an opioid "for the pain," then stop breathing in a chair. Respiratory depression with opioids and other CNS depressants is a labeled warning.
Antacids with aluminum or magnesium drop absorption. Separate by about two hours. Food is otherwise fine. Alcohol is extra sedation you did not need.
Mood change, suicidal thinking, and a new rash (DRESS is on the class radar) are stop-and-call events. Peripheral edema is common enough that a new shoe size is worth a mention.
06 Come down over at least a week if this is epilepsy
The insert wants a taper over a minimum of one week when you stop or add another antiseizure drug. Abrupt withdrawal can precipitate status in people who take gabapentin for seizures. Pain-only use still deserves a planned step-down if the daily total is high; rebound and insomnia are ugly enough.
Missed dose: take it when remembered unless it is near the next. Do not triple at bedtime. If you miss because of sedation, that is a titration or renal question, not a make-up pile.
Gabapentin is not metabolized in the liver. Hepatic disease is not the usual dose lever. Kidneys are.
| Absorption | Saturable absorption; higher doses absorb a smaller fraction. |
|---|---|
| Distribution | Not protein-bound in a clinically fussy way. |
| Metabolism | |
| Excretion | Renal; t½ 5-7 h, stretching to ~52 h when CrCl <30 mL/min. |
07 Coming off 400 mg capsules
Epilepsy: at least a one-week taper. Pain: still ask before you drop a high daily total overnight. Rebound insomnia and pain are ugly enough without a seizure risk.
Do not stop on Friday because you have a drink-heavy weekend. That is two CNS changes at once.
08 How to place a 400 mg capsule on a day kidneys still work
If the row is three times daily, space the capsules. Morning, mid-afternoon, evening is a common skeleton. Do not stack all three at 22:00. That peak is how people fall and how an opioid at 21:00 becomes a chair problem.
Food is fine. Aluminum or magnesium antacids need about two hours of space. Move the capsule or move the antacid. Write the times if both are three times a day.
Missed capsule: take it when remembered unless the next is due. Do not take 800 mg at bedtime to catch up. If you miss because you were too sedated, that is a titration or renal question. See the titration margin.
Alcohol is extra sedation. So is a leftover benzodiazepine. The labeled warning is about CNS depressants as a class, not only about named opioids.
Horizant and Gralise stay on their own food rules. Do not convert them into this 400 mg Neurontin rhythm.
09 Opioids, sleepers, and a 400 mg capsule in the same hour
Oxycodone at 21:00 plus 400 mg at 21:00 is a pair the insert already warned about. A clinician may separate the times or lower one drug. This leaf will not pick 19:00 by email.
Gabapentin is not metabolized in the liver. Hepatic disease is not the usual lever. Kidneys are. That is why a "my liver is fine" shrug does not clear a high creatinine.
Do not add an unmarked muscle relaxant from a drawer to "help the nerve pain" on day two of a ramp. Sedation stacks.
If you also take the fluoxetine 40 mg capsule, say both names. They are different stories. The pharmacist still needs the list.
10 Shoes that do not fit, and a rash that should stop the climb
Peripheral edema that changes shoes is common enough to mention. DRESS is uncommon and urgent. A spreading rash during a climb is a call, not an uptitration.
Mood change belongs in the same week as a new 400 mg step. Do not treat it with a leftover benzodiazepine from a drawer. Sedation stacks. The labeled warning is about CNS depressants as a class, not only about named opioids.
When the 90-count refill arrives, reread the renal row if weight or creatinine moved. A bottle that was honest last winter can be an overdose pattern now.
11 Ninety 400 mg capsules on the literacy strip
Ninety 400 mg capsules is the Virena lock. A 300 mg sixty-count is a different cash row and a different titration story. The strip is literacy. Virena does not dispense. GoodRx lives in the caption, not as a link on a store name.
| Pharmacy | Strength / count | Leaf note | Official page |
|---|---|---|---|
| Kroger | 400 mg x 90 | Titration ramps in the leaf body | Kroger desk |
| Safeway | 400 mg x 90 | Renal dose math before refill | Safeway desk |
| Harris Teeter | 400 mg x 90 | Sedation stacks with opioids | Harris Teeter desk |
| Albertsons | 400 mg x 90 | Neurontin brand is another NDC | Albertsons desk |
12 Creatinine clearance owns the 400 mg capsule's calendar
Subjects given a single 400 mg dose had a mean half-life about 6.5 hours when CrCl was over 60 mL/min and about 52 hours when CrCl was under 30. Plasma clearance fell from about 190 mL/min to 20. That is why the label's table exists. A 400 mg capsule three times daily on a CrCl of 20 is an overdose pattern, not a pain plan.
Cockcroft-Gault is the insert's outpatient estimate. Use actual clinical labs, not a phone eGFR screenshot from 2021. Hemodialysis removes gabapentin; a post-dialysis supplement is on the table. This leaf will not pick the 125-350 mg supplement for you.
Elderly people often sit in the middle rows without anyone saying "renal." Ask for the clearance before the next 90-count refill of 400 mg capsules.
13 Ramp the capsule, then ask the creatinine
Take 400 mg on the schedule that matches kidneys and indication. Separate antacids. Do not stop epilepsy treatment overnight. Elise dates the bind. She does not pick your CrCl row by email.
[email protected]. France: 15 or 112.
Space 400 mg capsules if the day holds more than one. Morning, mid-afternoon, evening is a skeleton. A 22:00 pile of three is a peak, not a strategy. Separate aluminum or magnesium antacids by about two hours. Food is otherwise fine. Alcohol and leftover benzodiazepines are extra sedation.
PHN climbs in 300 mg-shaped steps before a 400 mg TID board. Epilepsy starts differently and must come down over at least a week. Copying a pain stop onto a seizure medicine is how status gets written up. The titration margin is the ramp. The renal ink is the creatinine file.
When CrCl is 15 mL/min the daily range is 100-300 mg. One 400 mg capsule already overshoots that day. A single 400 mg study dose lasted about 6.5 hours when CrCl was over 60 and about 52 hours when CrCl was under 30. Sleepiness on a previously tolerated TID is often clearance, not a reason to add oxycodone.
Opioids plus gabapentin raise respiratory-depression risk. A chair slump after the pair is data. Horizant and Gralise are other products. Do not convert them milligram-for-milligram into this capsule.
Mail [email protected] if we treated 400 mg TID as safe at any creatinine. The >=60 mL/min row is where that rhythm lives.
Bring age, weight, sex, and a current creatinine when someone refills a 90-count. An ACE inhibitor week or an 8 kg weight loss can move the row. Do not wait for a chair nap to ask for Cockcroft-Gault. Do not invent every-other-day from a 400 mg bottle. QOD is not a printed row.