Wass looking forward to the METHYL form of B-12. I use sublingual for quick results. HOWEVER these JARROW brand tablets did not dissolve much at all during five minutes and were TOO HARD TO CHEW, really disappointing. Will have to go back to Spring Valley Walmart brand If I cannot find The METHYLCOBALAMIN In sublingual tablets that dissolve. At proper dosage it stops my arrhythmia saving A trip to dangerous doctors using dangerous prescriptions. Using 500 µg works for me will try 1000 µg next. Have used two of the 500 size with good results already. However, the 500 were cyanocobalamin, trying METHYLCOBALAMIN next, it should give quicker results than CYANO... I am a chemist/bacteriologist/mycologist, etc. and not associated with healthcare providers!!! arrhythmia is caused by different things. Mine was caused by Sam seltzers (out of business) poisoning my food. The poison, A pyrethrin compound is a neurotoxin sold as flying insect spray. Printed right on the can is the statement that it's safe to use around food; in the hands of an idiot it becomes dangerous. Researched this product carefully and thought it would be OK. Again, very disappointed this company would put out such a product. Really guys, it needs to dissolve quickly under the tongue. For now, it is back to Cyanocobalamin; Walmarts brand did dissolve quickly under the tongue. I still recommend methylcobalamin if you can find one that dissolves. Either kind will not absorb much from the digestive system until it gets to the very end section of the small intestine. With arrhythmia dissolving under the tongue gets into the bloodstream quickly. When the heart is jumping around, time is important. Find a good DO for treatment. If you find one let me know. This problem needs serious diagnosis as to cause. Treatment will vary based on that. Be careful about going to emergency entrance of hospital. My experience due to long term effect of eating at a restaurant and getting poisoned was devastating. Emergency tortured me two different ways. First was four days without anything liquid to drink, not even food with juice like fruit. I challenge you, if you do not think that is torture, try no drinks for four days. No water nothing. The second means of Torture was forcing me into an MRI process after I said I did not want that test. They said Dr.'s orders. Sound a bit like the medical experiment camps in Germany in the early 1940s? They checked to see how much pain people could tolerate before dying. The sound waves in the MRI were so devastating I was totally deaf for months. I was lying helpless on a stretcher and two goons shoved me in. Aside from the torture, they injected something like IL-8 or Cipro in huge amounts that turned healthy tendons into hardened like a rock so my hand can't work. That process took less than a week. IL-8 is an Inflammatory agent generally 100 times more concentrated in rheumatoid arthritis joints than healthy joints. Few things could cause this much damage that fast. I am mentioning this in case people coming out of emergency rooms across the country might be having serious problems they did not have when they went in. It would be a ruthless way to make money. If you go home with something you did not have that will ultimately require surgery like a joint replacement or treatment for cancer, you poor thing. You are not alone, there could be millions like you. If so, get the word out. Result of my Emergency Entrance visit includes ELBOW AND SHOULDER DAMAGE (influence of injections or pills ) PLUS HIP AREA TENDON DAMAGE. Permanent disability. You might be told that your problems from emergency treatment is a common result of the condition. Of course if they treat everybody that way, what would you expect? And, that would be their defense in court