Albert Barnes Commentary 2 Kings 8:1

"Now Elisha had spoken unto the woman, whose son he had restored to life, saying, Arise, and go thou and thy household, and sojourn wheresoever thou canst sojourn: for Jehovah hath called for a famine; and it shall also come upon the land seven years." — 2 Kings 8:1 (ASV)

The famine recorded here, and the king's conversation with Gehazi, must have occurred before the events related in 2 Kings 5. We can be sure of this because a king of Israel would not have entered into familiar conversation with a confirmed leper.

The writer of Kings probably collected the miracles of Elisha from various sources and did not always arrange them chronologically. In this case, the connection is found in the nature of the miracle: just as Elisha prophesied plenty on one occasion, so on another he had prophesied a famine.

Called for a famine - This is a frequent expression (compare the cross-references). God’s “calling for” anything is the same as His producing it (Romans 4:17).