If so, fear not, you're not alone. In fact, it would be quite difficult to be alone with this one. Despite its rather ominous-sounding title, ‘gargalesis' is actually “heavy tickling, often resulting in laughter”. So it's more than likely going to require at least two people to get a bad case of this condition.
And it has a sibling. To perform or receive a feathery ‘light tickling' (and actually, sometimes they're even worse) goes by the name, KNISMESIS. The names themselves have very scientific origins, coined in 1897 by a couple of psychologists clearly with too much time on their hands. As words, they're pretty rare – confined usually to medical journals and smarty-pants know-it-all blogs.
Also, if you've always wondered why we laugh when we get tickled, go here for the answer.