Monday February 9, 5:24 pm Eastern Time
U.S. FDA issues warning on antihistamine
WASHINGTON, Feb 9 (Reuters) - Janssen Pharmaceutica and the U.S. Food and Drug Administration (FDA) said on Monday they had issued a warning
to doctors about possible drug interactions with the antihistamine Hismanal.
Taken at higher-than-recommended doses or with some drugs, Hismanal can cause irregular heart rhythms or severe allergic reaction, the FDA said in a
statement. Janssen said it was changing the label on the drug.
''Hismanal is associated with risks of death due to irregular heart rhythms when taken with certain other drugs and when used at higher than the recommended
labeled dose,'' the FDA statement said.
''The new labeling provides information about a specific warning against simultaneously using Hismanal with other types of drugs such as the hypertension
drug Posicor (mibefradil) and the antibiotics Biaxin (clarithromycin) and TAO (troleandomycin).''
Other drugs Hismanal should not be taken with include HIV protease inhibitor drugs such as Crixivan (indinavir), Norvir (ritonavir) and Viracept (nelfinavir),
anti-depressants in the SSRI class such as Prozac, known generically as fluoxetine, Zoloft or sertraline and Paxil or paroxetine.
It should also not be combined with Zyflo or zileuton, an asthma drug, or with grapefruit juice, which is known to make some drugs act more effectively in the
body.
''These recommendations are based on the potential of these drugs and grapefruit juice to interfere with the body's handling and metabolism of Hismanal,'' the
FDA said.
''The new labeling also emphasizes that patients with liver disorders would not take Hismanal.''
Hismanal, known generically as astemizole, is marketed by Janssen, a Johnson & Johnson Inc. (JNJ.N.) subsidiary.
''Worldwide experience indicates that Hismanal is safe and effective when used in accordance with its labeling,'' the letter to doctors from Janssen read.
In May, Swedish doctors writing in the Lancet medical journal said astemizole and another antihistamine, loratadine, showed markedly high rates of sudden
cardiac death and other severe reactions.
The drugs are alternatives to terfenadine, which was the first prescription antihistamine to relieve hay fever symptoms without causing drowsiness. But its use is
now restricted because of safety concerns. The FDA has proposed removing terfenadine from the market.
Astemizole is already under review in Britain. |
