The longest words in Spanish are not so horribly long. ¨Electroencefalografista¨ (the person who administers an EEG test) is the longest, according to the RAE (official source on the Spanish language).
The article I found that in also tells about the longest word in the world-- the name of the worlds largest protein with 189,819 letters.
If you have nothing to do for the next 3+ hours you can try to watch this video of someone reading the name! In Spanish, it is much more practical-- they just call it ¨titina.¨