Does smoking cannabis affect any symptoms of dyslexia?

It might: Thc is known to diminish cognitive processing speed (in pilots, measurable for up to 24 hours after the equivalent of a single joint of mid-strength marijuana). As dyslexics often need to compensate by rapidly processing information in an alternate fashio than others, cannabis is likely to make the results of dyslexia appear worse--even though it's not likely to worsen the condition itself.

Cannabis: Eventually, with continued use, as it affects your cognitive functions.