Science / Medicine : Java May Hinder Ex-Smokers

Researchers at San Francisco General Hospital reported last week that smokers who recently kicked the habit may be unusually sensitive to caffeine, suggesting that their tendency to be anxious and irritable from nicotine withdrawal may be magnified by a cup of java.

Dr. Neal Benowitz and his colleagues studied 68 men and women who were going to try to quit smoking. The amount of caffeine in the blood of those who stopped smoking was more than 2 1/2 times higher after they quit than before, even though their caffeine consumption remained the same or even decreased, the researchers reported in the British Medical Journal. By comparison, there was no change in the amount of caffeine in the blood of those who did not quit, the researchers said.

The tar in cigarette smoke is believed to accelerate the breakdown of a number of drugs, including caffeine, said Benowitz, so when someone quits smoking, the caffeine may not be broken down as quickly.