I’m currently writing a stand-up comedy act and I need some nasty sounding diseases and side-effects. I’ll even take words that sound like horrible diseases and aren’t at all. (like Catholism or Kasparitis)
Here is what I got so far:
Syphillis
Leprosy
Scrofula
Ebola
Epilepsy
Lupus
Kuru
Lumbago
Scorbutus
Chancroids
Chagoma
Fistula’s
Constant bleeding from both eyes
Yeast infection of the mouth
Cancer of the Testicles
Instant and sudden death
So help me out a bit
botulism
Yellow fever
Scarlet fever
Ruematic fever
Pleurisy
Bubonic plague
Small Pox
Typhoid
Diptheria
Malaria
Consumption
Ricketts
Scurvy
psorisis
Shingles
Pnemonia
Bronchitis
Mastitis
Ring worm
Mumps
Measles
Protesis
Tetnis
AIDS
pardon spelling errors
I found this gem while doing research for my Sociology project on drug abuse prevention for American youth.
From http://www.teenchallenge.com/drugs/cocaine.cfm?doc_id=5#effects
(Bolding mine)
Sudden and lingering death! Wow. Interesting.
Bullous pemphigoid
Onychogryposis
Necrotizing fasciitis
Xerophthalmia
Cerebrotendinous xanthomatosis
Whistling face syndrome
Burning vulva syndrome
Gangrenous stomatitis
Tsutsugamushi disease
Poikilodermatomyositis
Genital erosive lichen planus
Pityriasis furfuracea
I’ve always been fond of purpura.
Photonomia
Progenolepsis
Parasyntrax
Ortholecsis
Metapropellis
Ordinascepsis
etc.
If you were a horse, you could have strangles. Or windpuffs. Or sweeney. Or galls. Or (pick one) parrot mouth or monkey jaw. Or founder.
** Anal Scurvy **
Idiopathic thrombocytopenic purpura
Pheochromocytoma (hundreds of extra adrenal glands - they get twitchy)
http://www.merck.com/mrkshared/mmanual/section2/chapter9/9d.jsp
Congo Crimean Hemorrhagic Fever (Hemorraghic, like the name says)
http://www.stanford.edu/group/virus/pox/2000/Congo.html
Epididymitis (Grab your balls, we’re going bowling -really!)
http://www.uro.com/epididym.htm
Ankylkosing Spondylitis.
Bilharzia
Euthanasia
Anthrax
Dengue fever
Lockjaw
Trachoma
Chlamydia
Typhus
Typoid fever
Legionaire’s Disease
Diptheria
Chron’s Disease
Colitus
Dracontiasis
River Blindness
Irritable Bowel Syndrome
Rabies
Ringworm
Scarlet fever
Montezeumas Revenge
Rubella
Indigo
Scabies
Hepatitus
Phrenia
Lombago
African Sleeping Sickness
Gingivitus
Scrotal Cinematic Multiplex
Intestinal Worms
Whooping Cough
Neonatal Tetanus
Oroya Fever
Cholera
Salmonellosis
Rabbit fever
Ciguatera Poisoning
Rocky Mountain Spotted fever
Trichinosis
Yellow fever
Sounds like your comedy act is a real hoot, eman! 
Pneumonoultramicroscopicsilicovolcanoconiosis, the longest word in the English language.
I’ve always been fond of this list.
Some highlights:
scrumpox
scrotal pustules
Fatal familial insomnia
Transmissible spongiform encephalopathy
Chronic inflammatory polyneuropathy
Progressive multifocal leukoencephalopathy
Smiley’s Syndrome
Creeping scarfoma
Ronald MacDonald Disease
Chronic burping with boils
One-legged Arrrrrr Syndrome (OAS)
The Fizzles
Craps Three Disorder
Festering Whonuts
Mister Wilson’s Disease
Pustule Migration Complex
The Screaming Abdabs
Frond
Mad Kitten Disease (aka Brown-Wurlitzer Syndrome)
…and worst of all…
Second-degree Oojahs with Complications
[shudder]
So Many Band Names!
Scrofula
Herpetic whitlow
And for your act, think about that massage parlor with the “happy ending.” Safe, right? Wrong!