Sitagliptin (Januvia) and metformin (Glucophage, and others) are now available in a single tablet (Janumet - Merck) for treatment of type 2 diabetes. The combination is approved by the FDA for use in patients not adequately controlled by sitagliptin or meformin alone or in those already taking both drugs. Metformin is also available in combination with the thiazolidinediones pioglitazone and rosiglitazone and with the sulfonylureas glipizide and glyburide.

MoviPrep (Salix) is a new polyethylene glycol (PEG)-based bowel cleansing preparation approved for use in adults prior to colonoscopy. It contains ascorbic acid, which acts as an additional cathartic and flavoring agent, and requires a lower volume of fluid (3 L compared to the traditional 4 L) than most other PEG products. HalfLytely is an FDA-approved 2-L PEG product, but it must be taken with bisacodyl.

Gadolinium-based contrast agents, which are used mainly for magnetic resonance imaging and angiography, were first introduced partly because of the discovery in the 1990’s that iodine-based contrast agents could cause nephrotoxicity and acute renal failure. Some recent reports have suggested, however, that gadolinium-based agents may also be nephrotoxic.1 One patient who developed acute renal failure after use of gadolinium-based contrast had a renal biopsy that showed acute tubular injury.2

Moreover, after exposure to gadolinium-based contrast, some patients with severe renal insufficiency, or liver disease with any degree of renal insufficiency, have developed nephrogenic systemic fibrosis, with sclerodermalike changes in the skin, connective tissues and other organs, which has sometimes been fatal.3,4 The mechanism is unknown; release of free gadolinium ions, which are toxic, has been suggested.5

Gadolinium-containing contrast agents are marketed in the US as Magnevist, MultiHance, Omniscan, OptiMARK, and ProHance (www.fda.gov). In patients with renal insufficiency, especially those requiring dialysis, use of any contrast agent should be avoided if possible.

1. C Briguori et al. Gadolinium-based contrast agents and nephrotoxicity in patients undergoing coronary artery procedures. Cath Cardiovasc Interven 2006; 67:175.

2. H Akgun et al. Are gadolinium-based contrast media nephrotoxic? A renal biopsy study. Arch Pathol Lab Med 2006; 130:1354.

3. AS Boyd et al. Gadolinium deposition in nephrogenic fibrosing dermopathy. J Am Acad Dermatol 2007; 56:27.

4. A Deo et al. Nephrogenic systemic fibrosis: a population study examining the relationship of disease development to gadolinium exposure. Clin J Am Soc Nephrol 2007; 2:264.

5. T Grobner and FC Prischl. Gadolinium and nephrogenic systemic fibrosis. Kidney Int 2007 May 16; epub ahead of print.

Download U.S. English