Ashley asked
What is the difference between gabapentin and Lyrica? Lyrica is too expensive and my doctor switched me to gabapentin
Answer
Lyrica (pregabalin) and Neurontin (gabapentin) reduce anxiety, pain, and seizure activity by binding to receptors in the central nervous system tissues.
Both are structurally related to GABA, a brain chemical that generally has a depressive or slowing effect (hence "gaba" in both generic names). Lyrica has been shown to be more potent than gabapentin, is currently brand name only, and is a controlled substance. Because of the cost and similar mechanism of action, it may be appropriate to attempt gabapentin therapy instead of Lyrica in some patients.
Gabapentin
Gabapentin was first approved by the FDA in 1993 for seizures and in 2002 for nerve pain associated with Shingles. Usually the dose for gabapentin and Lyrica is titrated over time to find the right dose and may be given up to three times daily. Lyrica is about six times more potent than gabapentin and has been shown to be beneficial in patients where gabapentin stopped working.
Lyrica
Lyrica was first approved by the FDA in 2004 and is therefore quite a bit newer and therefore more expensive than gabapentin. Because Lyrica is only available as a brand name drug, the lack of competition allows the price to stay relatively high. The generic market for Lyrica (pregabalin) should open up some time in 2018 and will eventually lower the price significantly. Lyrica manufacturer, Pfizer, has received FDA approval for an extended release version of Lyrica that will allow for once daily administration. This will help Pfizer offset the loss of exclusivity on Lyrica in order to maintain some profits.
Lyrica can be used in treatment of nerve pain in patients with fibromyalgia, diabetes, and post-Shingles. Lyrica is the first drug FDA-approved for treatment of fibromyalgia, but Cymbalta (duloxetine) and Savella (Milnacipran) have since been approved as well. Gabapentin has been used off-label for fibromyalgia.
Differences
One of the key differences with Lyrica and gabapentin is
that Lyrica is a Schedule V controlled
substance (least risk of abuse of all controlled substance classes). Being
a controlled substance requires Lyrica to face enhanced restrictions due to
increased risk of abuse as compared to non-controlled medications. Although
gabapentin is not a controlled substance in most states, it has been shown to
be abused by some patients, especially when taking
opioids at the same time. Because of this, some states are electing to
change gabapentin to a controlled substance, like Lyrica.
