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Could you be thinking of the dragon article, "Totem Creatures of the Far Realm: The Aberrant Souls", from edition 394? It provided the following table.

If you wish to add cosmetic changes to your character to show the changes caused bythe aberrant connection, some options arelisted below. You can choose a trait that mostexpresses the chosen totem creature, or roll1d10 to determine what characteristic develops.
For a truly volatile body, you can choose toroll every time you gain a level, with a new trait replacing or adding to the old one.

1 Your eyes become entirely black or are covered in a milky white film. Neither effect impairs your ability to see.
2 Your hair is replaced with tentacles.
3 Your eyes bulge from their sockets, and can be extended on short stalks at will.
4 Weeping sores appear on some part of your body.
5 The palms of your hands sprout tiny mouths, and your fingers elongate.
6 Patterns of color move across your body as if something were crawling under your skin.
7 You no longer have eyes—instead, you have smooth skin where your eyes would be. You can still see normally, and can still be blinded.
8 Your skin is cold and slimy, occasionally leaving a thin film on things you touch.
9 When you bleed, your blood is black and viscous, like crude oil.
10 R eroll twice, taking two unique traits (ignore any other rolls of 10 or conflicting traits) 

 

 Honestly, you're better off just roleplaying the effects of madness rather than rolling on a table. Much easier to come up with something that's appropriate to the specific scene or situation the character's in. (Also less likely to irritate the rest of the party.)