What does it mean, if you know? And the actual words for what the card is?
I can't say for
sure because add:e is an abbreviation (the colon is an old-fashioned mark for abbreviation) and I don't know exactly what it's abbreviating. Gehæ isn't even a real word as far as I can tell; it seems like you might have just got part of a word by accident, though, because gehælan is a variant of hælan, meaning 'to heal'. Its conjugated forms include gehæl "heal!", gehæle "I heal", and gehæled "healed", as examples. "Healing" as a noun form is normally just hæling, although in the genitive ("of" case, as your translation implies), hælinge. The other two words are more or less comprehensible, though: blæc means "black" (or "to bleach", the connecting concept is "colourless" - ancient language seems to have been weirdly ambivalent about black and white), and, while I don't
think that "blæces" is an ordinary conjugation of it, blaces (with the regular 'a') is the correct genitive form. Now, drenċ, on the other hand, is exactly right: It means "drink" (although "drink" apparently comes from the related word drynċ instead) and has been used for "potion" (both medicine and poison). It's in the nominative, though, so it clashes with the case of the adjective 'black', and also doesn't fit the case your translation implies; it would be better written drenċes in context. That said, I believe the ċ is a modern development, and the word was actually written with a normal c at the time - it represents that it's pronounced "ch" instead of "k". Just as that implies, the word is pronounced "drench", and "drink" and "drench" are etymologically related, incidentally.
So to sum up, the way I would personally write "of healing and potions" would be
hælinge and drences (no need for a specific preposition, the genitive case does the work in old english), although I think a real typesetter titling a book would probably put
Hælinge ⁊ Drences, using the standard abbreviation for 'and' of the time.
That said, I may have made some kind of obvious mistake, as I don't have formal training in old english translation. It's possible someone else will say that this is almost as wrong.