Warfarin sodium (Coumadin, and others) and other coumarin anticoagulants prevent thrombosis, but patient response is highly variable and overanticoagulation can lead to hemorrhage. Genotyping patients for single nucleotide polymorphisms (SNPs) that affect coumarin metabolism and sensitivity may help clinicians estimate the therapeutic warfarin dose. The FDA has added a note to warfarin labeling recommending lowrange doses for patients with such genetic variations. Commercial tests for these variants are now available and cost about $500 per test.

Tinidazole (Tindamax - Presutti Labs), an oral antiprotozoal drug similar to metronidazole (Flagyl, and others), has been approved by the FDA for treatment of trichomoniasis in adults and for treatment of giardiasis, intestinal amebiasis and amebic liver abcess in adults and children more than 3 years old. Tinidazole has been widely used outside of the US for decades under the trade name Fasigyn (Pfizer).

The FDA has approved the oral adenosine triphosphate-citrate lyase (ACL) inhibitor bempedoic acid for use alone (Nexletol – Esperion) and in a fixed-dose combination with the cholesterol absorption inhibitor ezetimibe (Nexlizet) as an adjunct to diet and maximally tolerated statin therapy in adults with heterozygous familial hypercholesterolemia (HeFH) or established atherosclerotic cardiovascular disease (ASCVD) who require additional lowering of LDL-cholesterol (LDL-C). Bempedoic acid is the first ACL inhibitor to be approved in the US.

Psoriatic arthritis is a chronic inflammatory arthropathy associated with psoriasis. A recent review found that about 20% of patients with psoriasis have psoriatic arthritis. Updated guidelines for treatment of psoriatic arthritis have recently been published.

A reader expressed disappointment that our recent listing of “Some Warfarin Drug Interactions”1 did not include acetaminophen. Perhaps it should have. Acetaminophen can increase the anticoagulant effect of warfarin, particularly with continued use, but it does so inconsistently. The mechanism of this interaction has not been established, but may be related to an acetaminophen metabolite inhibiting vitamin K-epoxide reductase, the target for warfarin’s anticoagulant effect.2Patient susceptibility varies, possibly on a genetic basis; occasional use of acetaminophen generally has little or...

Rheumatoid arthritis (RA) is prevalent in 0.5% of adults in the US; it is about 2.5 times more common in women than in men. Guidelines for treatment of RA from the American College of Rheumatology were recently updated. The goal of treatment is to minimize disease activity and prevent irreversible joint damage.

View Expanded Table: Some Conventional DMARDs for Rheumatoid Arthritis

Ursodiol (ursodeoxycholic acid), a naturally occurring bile acid, will soon be marketed in the USA as (Ciba-Geigy), an oral drug for dissolution of gallbladder stones. The labeling for the drug, which has been available in other countries for the past ten years, will restrict its use to dissolution of radiolucent, noncalcified gallbladder stones less than 20 mm in diameter in patients who have refused or are at increased risk from surgery.

Primary hypothyroidism is usually the result of Hashimoto's (autoimmune) thyroiditis, thyroidectomy, or radioactive iodine therapy. Treatment of hypothyroidism with replacement doses of thyroid hormone is usually lifelong. Levothyroxine (LT4; synthetic thyroxine; Synthroid, and others) is the drug of choice.1

The FDA has approved Relyvrio (Amylyx), a fixed-dose combination of sodium phenylbutyrate and taurursodiol, for treatment of amyotrophic lateral sclerosis (ALS). Sodium phenylbutyrate (Buphenyl, and others) has been available by prescription for years for treatment of urea cycle disorders. Taurursodiol (tauroursodeoxycholic acid), a derivative of ursodiol, is an over-the-counter bile acid supplement claimed to have neuroprotective benefits. Relyvrio is the third drug to be approved in the US for treatment of ALS; riluzole (Rilutek, and others) and edaravone (Radicava, Radicava...