‘‘We were really concerned to find that in four years the number of emergency department visits almost doubled, and these drinks are largely marketed to younger people,’’ said Al Woodward, a senior statistical analyst with the Substance Abuse and Mental Health Services Administration who worked on the report.

Emergency physician Steve Sun said he had seen an increase in such cases at the Catholic hospital where he works on the edge of San Francisco’s Golden Gate Park.

‘‘I saw one young man who had mixed energy drinks with alcohol and we had to admit him to the hospital because he was so dehydrated he had renal failure,’’ Sun said. ‘‘Because he was young he did well in the hospital, but if another patient had had underlying coronary artery disease, it could have led to a heart attack.’’

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