The following article discusses the use of topical ketamine 0.5% (5 mg/ml) gel, applied as a thin film two to three times daily over the skin where pain was severe. Topical ketamine reduced pain for patients with postherpetic neuralgia with no systemic side effects.

Neurology 2003;60:1391-1392

Topical ketamine treatment of postherpetic neuralgia

Dianna Quan, MD, Mary Wellish, BS and Donald H. Gilden, MD
Departments of Neurology (Drs. Quan and Gilden, M. Wellish) and Microbiology (Dr. Gilden), University of Colorado Health Sciences Center, Denver.

No abstract available. Click here to purchase the full article on line.

The following randomized, double-blind, placebo-controlled study assessed the analgesic efficacy of topical administration of 3.3% doxepin hydrochloride, 0.025% capsaicin or a combination applied daily for 4 weeks in 200 adult patients with chronic neuropathic pain, and reported that all three preparations significantly reduced overall pain.

Br J Clin Pharmacol 2000 Jun;49(6):574-9

Topical application of doxepin hydrochloride, capsaicin and a combination of both produces analgesia in chronic human neuropathic pain: a randomized, double-blind, placebo-controlled study.

McCleane G
Pain Clinic, Craigavon Area Hospital, 68 Lurgan Road, Craigavon, BT63QQ5, N. Ireland.

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