The 59-year-old was taken ill and sought medical help on Friday and was diagnosed with what the club describe as "a hypertensive crisis". Hypertension is another name for high blood pressure.
A statement on the club's official website confirmed: "Next week, the head coach will have to be treated in a Moscow clinic."
Blokhin, who led Ukraine in this summer's European Championship, last week replaced Yuri Semin at Dynamo but with the intention of still taking charge of his country's World Cup qualifiers against Moldova and Montenegro next month.
During his playing days as a striker, he won 112 caps for the then USSR team, scoring 42 goals, He also played over 400 times for Dynamo with a scoring record close to a goal every two games.