Skip to main content
PharmSpace

Class Explorer · Neurology

Gabapentinoids

Bind the alpha-2-delta subunit of voltage-gated calcium channels and reduce excitatory transmitter release. Named after GABA and acting nowhere near it.

Members

Also in this class: Pregabalin. Full pages arrive as the library grows.

Compare the members

Gabapentin
Absorption
Saturable, falls at higher doses
Renal handling
Entirely renal; dose tracks clearance

Shared across the class

Indications
Neuropathic pain · Focal seizures as adjunct · Restless legs syndrome · Generalised anxiety disorder (pregabalin)
Adverse effects
Sedation and dizziness · Peripheral oedema · Weight gain · Respiratory depression with opioids · Misuse potential
Contraindications
Known hypersensitivity
Monitoring
Renal function, which sets the dose · Sedation, gait and cognition, especially in older adults · Whether it is actually helping, judged after an adequate trial rather than continued indefinitely

What makes each agent different

  • Pregabalin has linear, near-complete absorption; gabapentin's transporter saturates, so its bioavailability falls as the dose rises and splitting doses matters.
  • Both are renally cleared and both accumulate quietly in kidney disease, which is where their confusion and myoclonus come from.

The ankle oedema is a drug effect, not heart failure. Answering it with furosemide is a textbook prescribing cascade.

Combined with opioids these drugs contribute meaningfully to respiratory depression, a risk that took years to be recognised.

Last reviewed 2026-08-16 · Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed.