SIMILARITIES

  • Both medications are often used to treat neuropathic pain and epilepsy
  • Mechanism: Both work via inhibition of Ca+ influx and block release of excitatory neurotransmitters. However, exact mechanism not known!
  • Both drugs can be taken without food
  • Neither drug binds to plasma proteins
  • Both drugs are renally excreted and not metabolized by the liver (CYP Enzymes)
  • Half-life of both is ~6 hours

DIFFERENCES

Pregablin (Lyrica)

Gabapentin (Neurontin)

  • Also indicated for fibromyalgia, and generalized anxiety disorder.(Better for seizure reduction),
  • rapid absorption (peak concentration in 1-2hrs)
  • Absorption is linear (first order), therefore Pregablin plasma concentration increases proportionately with increasing dose.
  • slower absorption (peak concentration in 3-4hrs)
  • Oral gabapentin exhibits saturable absorption; pharmacokinetics less predictable (zero-order)
  • Gabapentin plasma concentration does not increase proportionally with increasing dose

**pregabalin may have some pharmacokinetic advantages over gabapentin; This may be the reason for improved pharmacodynamic effect.

REFERENCES

  1. Bockbrader HN, Wesche D, Miller R, Chapel S, Janiczek N, Burger P. A comparison of the pharmacokinetics and pharmacodynamics of pregabalin and gabapentin. Clin Pharmacokinet. 2010 Oct;49(10):661-9. doi: 10.2165/11536200-000000000-00000.