Possible side effects of Alka-Seltzer effervescent tablets: All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome: Heartburn; nausea; upset stomach.
A myoclonic jerk is the brief, involuntary twitching of a muscle or group of muscles. It may be caused either by a sudden muscle contraction, or a sudden lapse of contraction.
Cortical Myoclonus. Posted by @19midw19 in Brain & Nervous System, Feb 20, 2013. I am a 74 year old female who been diagnosed with Cortical Myoclonus or bodily jerks sometimes accompanied by restlessness day or night that can be triggered by uncomfortable thoughts or sensations, caffeine, certain artificial sweeteners and possible other chemicals.