Effervescent GlutaGain Cherry Flavor 465 gm. Effervescent Glutagain by Absolute Nutrition. Effervescent Glutagain is the only genuine effervescent glutamine product on the market today. Others just add carbonation to their glutamine. Only GlutaGain has the glutamine that's bonded to the effervescent molecule. With a 98% absorption rate, this all natural pharmaceutical grade product will power your workouts like no other. 98% ABSORPTION RATE, INCREASES GROWTH HORMONE RELEASE, PREVENTS MUSCLE FATIGUE, INCREASES NITROGEN RETENTION, BIGGER AND FULLER PUMPS, AND WON'T UPSET THE STOMACH.