Actually, no: a lipogram is not a painful medical test.

From The Millions, December 20, 2016:

“The entire manuscript was written with the E-type bar of the typewriter tied down; thus making it impossible for that letter to be printed. This was done so that none of that vowel might slip in, accidentally; and many did try to do so!”  Abe Books tells the tale of Gadsby, a self-published 50,000-word novel written without using the letter “e.” Its author, Ernest Vincent Wright, won some notoriety when he accomplished the feat – called a lipogram – in 1939, although it’s unlikely Wright could have foreseen that individual copies of his book would eventually fetch prices upward of $1,200. And if it’s literary hijinks you’re after, definitely read our own Anne Yoder on the work of Georges Perec, who wrote a lipogram of his own in 1969.