Why does gabapentin need to be titrated

Several cross-sectional studies have reported gabapentin being used in subtherapeutic doses among most patients. The cornerstones of effective pharmacotherapy are the right patient, the right drug, and the right dose. If an analgesic medication is being used at a suboptimal dose, oftentimes a knee-jerk reaction is to add another analgesic for synergy. While this may well be indicated under appropriate circumstances, it is inappropriate without maximizing the dose of each single agent with careful attention to dose titration in order to minimize toxicity of each add-on.

This adds to polypharmacy, increased costs, and the pain remains inadequately treated. Pharmacists as medication experts can collaborate with prescribers to optimize the rational use of gabapentin in neuropathic pain. Receptor binding causes presynaptic inhibition of excitatory neurotransmitter release i. Gabapentin has saturable, non-linear absorption kinetics, where bioavailability decreases as the dose increases.

Pregabalin boasts a binding affinity for the alphadelta receptor that is six times greater than that of gabapentin. Patients should be aware of the therapeutic dosing for neuropathic pain to establish realistic expectations and improve compliance and likelihood of remaining on therapy.

If dose increases along the titration cause intolerable side effects such as dizziness or drowsiness, this can often be overcome by reducing back to the previous dose and escalating more slowly over a longer period of time.

Another mishap with gabapentin that contributes to treatment failure is when patients take it on an as needed basis. Gabapentin exhibits its activity by impeding calcium trafficking and is required to be present at the alphadelta receptor for hours in order to ensure efficacy. This is another area that pharmacists can educate patients at initiation of therapy to improve compliance. Despite its therapeutic role in neuropathic pain, gabapentin produces psychoactive effects and has an abuse liability.

Gabapentin abuse typically involves taking higher doses in a single administration. The median single dose for gabapentin abuse is mg, which is 3 times the maximum recommended single dose of mg. Alcohol use disorder is not generally a predictor of gabapentin abuse. In conclusion, pharmacists as medication experts are well-poised to educate prescribers and patients on therapeutic dosing of gabapentin to optimize its rational and appropriate use for treating neuropathic pain.

This commentary was collaboratively written with Shannon Donovan and Dr. Mena Raouf. This article is the sole work of the authors, and the stated opinions or assertions do not reflect the opinions of employers, employee affiliates, or any pharmaceutical companies listed. Treatment of neuropathic pain: an overview of recent guidelines.

Am J Med ; Suppl :S22— Pharmacotherapy for neuropathic pain in adults: a systematic review and meta-analysis. Lancet Neurol. Backonja M, Glanzman RL. Download PDF. Introduction Gabapentin Neurontin has FDA indication to treat postherpetic neuralgia and partial onset seizures.

Consistent, though less compelling clinical evidence supports its use for neuropathic cancer pain, pain associated with HIV infection, chronic back pain and others readers wanting more in depth research findings are urged to consult Reference 1. Due to this emerging evidence, it is widely used for the treatment of neuropathic pain. The exact mechanism and site of action of gabapentin is unknown. Gabapentin is generally well-tolerated, easily titrated, has few drug interactions, and does not require laboratory monitoring.

However, cost may be a limiting factor for some patients. See Fast Fact for a comparison of gabapentin with pregabalin a similar neuropathic analgesic. Adult Dosing Gabapentin is started at low doses mg to mg total daily and increased by — mg every days to effect. A typical schedule might be: day mg nightly; day mg twice daily; day mg twice daily; day 8 onwards: mg three times a day. The usual effective total daily dose is mg, administered in three divided doses per day.

Titration should proceed more slowly in elderly patients. If gabapentin is discontinued, it should be done over a minimum of a week to prevent withdrawal seizures. Pediatric Use There is limited data available assessing its effectiveness in neuropathic pain in children. The American Pain Society recommends that gabapentin be considered for pediatric neuropathic pain especially when concurrent analgesics are found to be too sedating. Dosing in Renal Failure Gabapentin doses must be reduced for patients with renal insufficiency.

Adverse Reactions Sedation, confusion, dizziness, and ataxia are the most common side effects, especially with rapid dose titration.