text: how do i know if i have a tapeworm gnawing on my brain?   1) first two answers obviously don't know shit about anything. cisticercosis is the systemic (generally cns based) form of taenia (vs. cestodiasis, the intestinal form), presented not in its adult form but as either an escolex or an oncosphere. now those are resistance forms of the parasite so it wouldn't really be eating your brain.  2) you would have considerable unspecific symptoms you could relate to practically any degenerative/inflammatory syndrome in the brain, from seizures to fever to severe mood changes to intracraneal hypertension, etc etc.  3) if lodged within brain parenchyma or brain circulation you'd feel no pain (the brain itself has no sensitive endings but the meninges do). in which case they could also clog small vessels and lead to cerebrovascular events ("strokes").  it's quite uncommon in any case.