The Food and Drug Administration said Thursday that some doctors and pharmacies are getting confused by the similar names of an antidepressant and a blood-thinning medicine.

The FDA says it's not aware of any patients who took the wrong drug, but the agency says it has received 50 reports of medication errors, including at least 12 cases where doctors prescribed the wrong drug or pharmacies dispensed the wrong one. The two medications are Brintellix, an antidepressant, and Brilinta, a blood-thinning medication used to prevent death after a heart attack or severe chest pain or to prevent a second heart attack.

The agency says it has been receiving reports of errors since Brintellix was approved in September 2013. Both drugs are tablets with the letter T stamped on them, and in some cases, both are yellow.

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The agency is suggesting doctors write out the generic name of the drug and the ailment for which it's being prescribed. Brintellix, an antidepressant taken once a day, is also known as vortioxetine. It's sold in the U.S. by Japanese drugmaker Takeda Pharmaceuticals, which reported $42 million in revenue from Brintellix in its latest quarter.

Brilinta, a blood thinner taken twice per day, is also called ticagrelor. It was approved in 2011, and maker AstraZeneca PLC said second-quarter U.S. sales of the drug totaled $101 million.

Companies propose names for their own drugs before they are approved. Those names are reviewed by the FDA's Division of Medication Error Prevention and Analysis, or DMEPA, which compares the name to drugs that are on the market and those still under FDA review.

The office creates a list of names that could be confused with the name of the proposed drug. It considers factors including the spelling of the new drug, the way it will be pronounced by people with different accents, and how the name will look when it's written by hand. The agency uses a variety of handwriting samples to see if the name of the new drug might look like a different drug in certain peoples' handwriting.

The FDA also rejects names that can mislead consumers by making a drug sound uniquely effective, and it doesn't allow names that are "overly fanciful." The agency says it reviews 400 proposed drug names every year and rejects about a third of them.

The FDA posted these tips for patients to help ensure that they don't mistakenly take the wrong medicine:

Check your prescription to ensure that the correct medication was dispensed.



Look at the name on the bottle.



Inspect the appearance of the tablet.



Know why you are taking it.



Ask questions to your health care professional if the name on the prescription, description of the medicine's use, or appearance of the medication is different from what you expect.

While both drugs come in tablet form and in some cases have the same color, there are differences to look out for.

Brintellix is a tear-shaped tablet stamped with the letters "TL." Each tablet has a number stamped on it to indicate the dosage (for example, "5" for the 5 mg tablet). The color varies depending on the dose and may be pink, yellow, orange or red.

Brilinta is a round, yellow tablet with "T 90" stamped on it.

Warnings over confusion based on drug names seem to be rare. But they do happen. In 2011, the agency said it had learned of more than 200 medication errors involving Risperdal, an antipsychotic, and Requip, which treats symptoms of Parkinson's disease and restless legs syndrome. The FDA said five patients were hospitalized when they were given the wrong drug.

The FDA noted that their brand names and generic names were somewhat similar: Risperdal is also known as risperidone, and the generic name for Requip is ropinirole. It also asked manufacturers Johnson & Johnson and GlaxoSmithKline PLC to change their packaging so they looked less alike.