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 recent "PROVE IT" trial in patients with coronary heart disease showed clinical benefits associated with reducing LDL cholesterol concentrations lower than the 100 mg/dL (2.59 mmol/L) or less that had been considered optimal.

The FDA has approved Viekira Pak (Abbvie), a fixed-dose combination of two new direct-acting antiviral agents (ombitasvir, paritaprevir) with the pharmacologic enhancer ritonavir in one tablet, co-packaged with a third new direct-acting antiviral agent (dasabuvir) in a second tablet, for oral treatment of chronic hepatitis C virus (HCV) genotype 1 infection. Genotype 1 is responsible for 70-80% of HCV infections in the US.

Three oral poly(ADP-ribose) polymerase (PARP) inhibitors have been approved by the FDA for treatment of advanced, recurrent ovarian cancer. Olaparib (Lynparza – AstraZeneca), niraparib (Zejula – Tesaro), and rucaparib (Rubraca – Clovis) are each approved for somewhat different indications and for patients with different biomarkers (see Table 2).

The FDA has approved lumateperone (Caplyta — Intracellular Therapies), an oral second-generation antipsychotic, for once-daily treatment of schizophrenia in adults. It is the 13th second-generation antipsychotic drug to be approved by the FDA for this indication.

Ramelteon (Rozerem - Takeda), a melatonin receptor agonist, has been approved by the FDA for treatment of insomnia characterized by difficulty falling asleep. Unlike all other prescription hypnotics, which are classified as schedule IV drugs, ramelteon is not a controlled substance.

The FDA has approved the marketing of pitavastatin (Livalo – Kowa), an HMG-CoA reductase inhibitor (“statin”), for treatment of primary hyperlipidemia or mixed dyslipidemia. It has been available in Japan since 2003. All of the statins now available in the US are listed in the table on page 58.

The drugs of choice for treatment of viral infections (other than HIV) and their dosages are listed in Tables 1-6 on the pages that follow. Some of the indications and dosages recommended here have not been approved by the FDA. Vaccines used for the prevention of viral infections are discussed elsewhere.

Alzheimer's disease (AD) is the most common cause of dementia, but cognitive decline is also associated with other neurological conditions such as Parkinson's disease, dementia with Lewy bodies, vascular dementia, and frontotemporal dementia.