The panel decided the stimulant methylxanthine found in the test samples of Yohan Blake, Allodin Fothergill, Lansford Spence and Marvin Anderson was not on the World Anti-Doping Agency (WADA) list of prohibited substances.
"Therefore the athletes were not liable under the WADA code," Kent Gammon, chairman of the disciplinary committee of the Jamaica Anti-Doping Commission, told reporters.
Gammon said the athletes ingested the stimulant in the form of capsules.
"They told the committee that they had done the checks that were necessary with the product and found that it was safe to consume," he said.
Gammon said lawyers for the four had presented "unassailable evidence and added: "We therefore upheld submissions from the attorneys, that the athletes had no case to answer."
The committee earlier had cleared Commonwealth Games 100 metres champion Sheri-Ann Brooks.
She also tested positive for the stimulant but the panel ruled the anti-doping commission had mishandled her second sample.
The world athletics championships begin in Berlin on Aug. 15.
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