The FDA has approved istradefylline (Nourianz — Kyowa Kirin), an oral adenosine A_2A receptor antagonist, for use as an adjunct to carbidopa/levodopa in adults with Parkinson's disease (PD) who experience "off" episodes. Istradefylline is the first adenosine A_2A receptor antagonist to be approved in the US; it has been available in Japan since 2013.

Acne is common among adolescents and adults. Guidelines for treatment of acne were last published by the American Academy of Dermatology in 2016.

The drugs of choice for treatment of fungal infections are listed in the table that begins on page 62. Some of the indications and dosages recommended here have not been approved by the FDA. More detailed guidelines for some of these infections are available online from the Infectious Diseases Society of America (www.idsociety.org).

Nonopioid drugs can be used in the treatment of many nociceptive and neuropathic pain conditions. For severe pain, especially severe chronic cancer pain, use of opioids may be necessary. Noninvasive nonpharmacologic treatments, including physical and psychological therapies, have been shown to improve pain and function in patients with some common chronic pain conditions and are unlikely to cause serious harms. A multimodal approach to analgesic therapy can increase pain control while reducing opioid use and adverse effects.

A new CDC guideline for prescribing opioids for pain recently became available. Nonopioid drugs for pain were reviewed in a previous issue.

The main goals of treatment of chronic obstructive pulmonary disease (COPD) are to relieve symptoms, reduce the frequency and severity of exacerbations, prevent disease progression, and reduce mortality. GOLD (Global Initiative for Chronic Obstructive Lung Disease) guidelines for treatment of COPD were updated recently. Treatment of acute exacerbations is not discussed here. Drugs available for treatment of COPD are listed in Tables 1 and 3.

Varenicline tartrate (Chantix - Pfizer) is now available for oral treatment of tobacco dependence. Some other drugs for this indication are listed in this article.

Intravenous immunoglobulin (IVIG) has 6 FDA approved indications and is prescribed off-label for many others. How many of these uses are justified is controversial.

The oral sphingosine 1-phosphate (S1P) receptor modulator ozanimod (Zeposia – Bristol Myers Squibb) has been approved by the FDA for treatment of adults with moderately to severely active ulcerative colitis. It is the first S1P receptor modulator to be approved for treatment of ulcerative colitis. Ozanimod was approved in March 2020 for use in adults with relapsing forms of multiple sclerosis.