Pregabalin (Lyrica - Pfizer), a structural analog of gamma-aminobutyric acid (GABA) similar to gabapentin (Neurontin - Pfizer, and others), which recently became available generically, has been approved by the FDA for treatment of neuropathic pain associated with postherpetic neuralgia (PHN) and diabetic peripheral neuropathy (DPN), and for adjunctive treatment of partial onset seizures in adults with epilepsy.

The FDA has approved the opioid agonist hydromorphone in a once-daily extended-release (ER) oral tablet formulation (Exalgo – Covidien) for the management of moderate to severe pain in opioid-tolerant patients requiring continuous, long-term therapy. Another hydromorphone ER formulation (Palladone – Purdue) was available previously, but was withdrawn from the market because taking it with alcohol could interfere with the extended-release mechanism and lead to rapid release of potentially lethal amounts of the drug ("dose-dumping").

Rivastigmine tartrate (Exelon - Novartis), a carbamate-based cholinesterase inhibitor, is now being marketed for treatment of patients with dementia due to Alzheimer's disease.

Recombinant human granulocyte colony stimulating factor (G-CSF, filgrastim) conjugated to polyethylene glycol (pegfilgrastim, Neulasta - Amgen) has been approved by the FDA for use in neutropenic patients with non-myeloid malignancies who are at high risk for infection. Filgrastim (Neupogen - Amgen) has been available in the US since 1991.

Zolmitriptan (Zomig - Zeneca), a selective serotonin (5-HT1)-receptor agonist, is now available in the USA for oral treatment of migraine headache. Zomitriptan structurally resembles sumatriptan (Imitrex - Medical Letter 34:91, 1992). Drugs currently used for acute treatment of migraine include injectable, oral and nasal spray formulations of sumaptriptan, injectable dihydroergotamine, dihydroergotamine nasal spray, ergotamine tartrate alone or with caffeine, and various analgesics. Anoterh 5-HT1-receptor agonist, naratriptan (Amerge - Gaxo Wellcome), has been approved by the FDA but has not...

Celecoxib, a selective COX-2 inhibitor, has been approved by the FDA for treatment of osteoarthritis and rheumatoid arthritis.

An injectable gel of hyaluronic acid (Restylane) has been approved by the FDA for correction of moderate to severe facial wrinkles and folds, such as nasolabial folds. Manufactured by Q-Med AB, a Swedish company, it has been used outside the US since 1996.

Readers have inquired about the effectiveness and safety of operations on the cornea to correct refractive errors and restore normal vision without glasses or contact lenses. Several different operations are now being used for this purpose.

Diclofenac sodium (Voltaren - Geigy), a nonsteroidal anti-inflammatory drug (NSAID) available in some countries since 1974, was recently introduced in the USA for treatment of rheumatoid arthritis, osteoarthritis and ankylosing spondylitis. It is being promoted as 'The number one prescribed antiarthritic in the world.'

A lidocaine 1.8% patch (ZTlido – Scilex) has been approved by the FDA for treatment of pain associated with postherpetic neuralgia (PHN). A lidocaine 5% patch (Lidoderm, and generics) was approved earlier for the same indication and has been used off-label for treatment of other types of localized pain. Both of these patches are available only by prescription. Lidocaine 4% patches (Aspercreme, IcyHot, and others) are available over the counter for back, neck, shoulder, and joint pain.