Citalopram (Celexa) and Escitalopram (Lexapro) Interact With Linezolid

On April 20, the FDA approved a revision to the safety labeling for citalopram hydrobromide and escitalopram oxalate (Celexa and Lexapro, respectively, made by Forest Laboratories) in tablet and oral formulations, advising that serotonin syndrome has been reported in two patients receiving concomitant doses of the antibiotic linezolid, a reversible nonselective monoamine oxidase inhibitor.

Citalopram and escitalopram are indicated for the treatment of depression.

8% Amino Acid Injection (HepatAmine) May Cause Aluminum Toxicity in Patients with Impaired Kidney Function

On April 29, the FDA approved revisions to the safety labeling for 8% amino acid injection (HepatAmine, made by B. Braun), warning that the product contains aluminum that may reach toxic levels with prolonged parenteral administration in patients with impaired kidney function.

Premature neonates are particularly at risk because they have immature kidneys and require large amounts of calcium and phosphate solutions that contain aluminum.

The FDA recommends frequent clinical and laboratory monitoring in at-risk patients.

The 8% amino acid injection is indicated as a source of nutritional support to patients with hepatic encephalopathy requiring parenteral nutrition and who are unable to receive general purpose amino acid injections.

Conjugated Estrogen Alone (Premarin) or With Medroxyprogesterone (Prempro, Premphase) Associated With Risk of Malignant Neoplasms

On April 20, the FDA approved extensive revisions to the safety labeling for conjugated estrogen tablets and vaginal cream (Premarin) and conjugated estrogen/medroxyprogesterone acetate tablets (Prempro, Premphase), advising of increased health risks associated with their use. The products are made by Wyeth Pharmaceuticals, Inc.

The FDA warned that estrogen with or without progestin should not be used for the prevention of cardiovascular disease.

Use of conjugated estrogen in women with intact uteri is associated with an increased risk of endometrial cancer, the greatest risk occurring with prolonged use (15- to 24-fold increased risk for 5-10 years of use or more) and persisting for at least 8 to 15 years after discontinuation.

Use of conjugated estrogen is also associated with an increased risk of breast cancer. Results of the Million Women Study in Europe showed an increased risk of mortality due to breast cancer among current users of estrogen alone or with progestin compared with therapy-naive patients.

Results of the Women's Health Initiative (WHI) study showed increased risks of myocardial infarction, stroke, invasive breast cancer, pulmonary emboli, and deep vein thrombosis in postmenopausal women aged 50 to 79 years during five years of treatment with conjugated estrogens (0.625 mg) combined with medroxyprogesterone acetate (2.5 mg), compared with placebo.

The WHI Memory Study showed an increased risk of probable dementia in postmenopausal women aged 65 years and older treated with combined conjugated estrogen and medroxyprogesterone acetate over four years.

The FDA notes that although other combinations and doses were not studied in the WHI clinical trials, the risks should be assumed to be similar. Estrogen with or without progestin should be prescribed at the lowest effective dose and for the shortest duration consistent with treatment goals.

The FDA recommends close clinical monitoring of women taking these products, including diagnostic measures such as endometrial sampling to rule out malignancies in all cases of undiagnosed persistent or recurring abnormal vaginal bleeding.

Conjugated estrogen vaginal cream is indicated in the treatment of atrophic vaginitis and lichen sclerosus et atrophicus of the vulva (also known as kraurosis vulvae).

Reviewed by Gary D. Vogin, MD

Related Links