A solstice can be two things, the summer solstice and the winter solstice. it's when the sun reaches its highest or lowest point in the sky at noon, marked by the longest and shortest days. however, an eclipse is when the earth, moon and sun align together blocking the sun's light which is why it's called an eclipse because it means hiding/blocking. :)
I think it is yes because they are both studies. Pharmakinetics is the study of an organism affecting a drug which could theoretically and potentially affect the result on how a drug affects an organism. I hope this helps you. I am not completely sure though. Just my logic speaking.