The ability of grapefruit juice to increase serum concentrations of drugs was first discovered during a study of the effect of ethanol on felodipine (Plendil) pharmacokinetics. Double-strength grapefruit juice used to disguise the taste of ethanol resulted in higher than expected serum concentrations of felodipine (DG Bailey et al, Clin Invest Med 1989; 12:357).

Patients with seasonal allergies often experience nasal itching and congestion, sneezing, rhinorrhea, and itchy, watery eyes. Oral, intranasal, and ophthalmic preparations are widely available over the counter (OTC) for relief of symptoms. Prescription products for management of allergic rhinitis and allergic conjunctivitis are reviewed separately.

Initial treatment of allergic rhinitis (AR) depends on the severity of symptoms and whether they are intermittent or persistent (see Table 1).

Older patients are especially susceptible to drug-induced cognitive impairment. They are more likely to be taking multiple drugs, to have higher blood levels of those drugs because of renal or hepatic dysfunction, and to have pre-existing cognitive problems that make it difficult to detect the role of drugs causing new symptoms or making old ones worse.

The FDA has approved mipomersen (Kynamro – Genzyme) and lomitapide (Juxtapid – Aegerion), each in addition to a low-fat diet and other lipid-lowering medications, to reduce cholesterol levels in patients with homozygous familial hypercholesterolemia (HoFH).

The physiologic changes that occur with aging can affect the pharmacokinetics and pharmacodynamics of many prescription and over-the-counter drugs, increasing the likelihood of adverse effects.

Acute cough (<3 weeks in duration) generally does not require pharmacologic treatment, especially in children. Suppression of productive cough may be harmful. Management of patients with cough should include elimination of any precipitating factor (e.g., cigarette smoking) and treatment of any underlying cause such as upper airway cough syndrome, gastroesophageal reflux disease, asthma, or other pulmonary disease.