JOURNAL ARTICLE

Replacement of gabapentin with pregabalin in postherpetic neuralgia therapy

Masataka Ifuku, Masako Iseki, Ikuhiro Hidaka, Yoshihito Morita, Syuji Komatus, Eiichi Inada
Pain Medicine 2011, 12 (7): 1112-6
21692969

PURPOSE: Although both gabapentin and pregabalin are first-line drugs for neuropathic pain including postherpetic neuralgia (PHN), no report has directly compared the magnitude of pain relief and the incidence of side effects of both drugs. By substituting gabapentin with pregabalin in postherpetic neuralgia therapy, we can compare the two drugs.

METHODS: In 32 PHN patients being administered gabapentin, without changing the frequency of dosing, the drug was substituted with pregabalin at one-sixth dosage of gabapentin. After 2 weeks, an interview was conducted about the visual analog scale (VAS) pain score, changes in the time of onset of action and duration of action after the substitution of drug and side effects (such as somnolence, dizziness, and peripheral edema). In addition, the dosage was increased while paying careful attention to the side effects (titration) in 22 patients who requested a dosage increase among those whom VAS pain score of ≥25 mm remained even after the substitution.

RESULTS: No significant changes were observed in VAS pain scores after the substitution of gabapentin with pregabalin. Regarding the time of onset of action and the duration of action after the substitution, the highest number of patients answered that no change occurred compared with the previous drug, followed by the patients who answered that the time of onset of action became quicker, and the duration of action became longer. The incidence of somnolence and dizziness showed no significant difference before and after the substitution, but peripheral edema showed a significant increase after the substitution. The level of side effects of both drugs was mild, and continued medication was possible. In the patient group where pregabalin dosage was increased, the VAS pain score decreased significantly compared with that before and after increase the dosage (P < 0.05). On the other hand, in nine out of 22 patients in the group where the dosage was increased, side effects appeared or were exacerbated. In two out of nine patients, it was necessary to reduce the dosage to the initial volume.

CONCLUSION: It was suggested that the analgesic action of pregabalin in PHN was six times that of gabapentin in terms of effectiveness in dosage conversion. Regarding the side effects, although the incidence of the peripheral edema was higher with pregabalin compared with gabapentin, this finding is not conclusive because the present study was conducted in a small number of subjects. Although pain reduction can be expected to increase with pregabalin dosage, it is necessary to increase the dosage gradually and carefully because of exacerbation of side effects.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
21692969
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"