Rock fever and island fever are colloquial terms for a form of mental distress said to mainly inflict mainlanders who move to isolated islands, especially any of the Hawaiian islands or Guam.[1][2] It is not a medical term or classification and has not been the focus of any serious research. It has been described as "an ailment" of feeling "stifled by [the island's] size and isolation", making its sufferers "anxious, irritated, desperate, and claustrophobic."[3][4] It is often ascribed to homesickness.[5] Rock fever has also been described as a feeling of isolation that could arise in any isolated place and afflict anyone, including native inhabitants.[6]
Although I was often warned about the isolation of living in Hawaii. That is the infamous 'rock-fever,' I have personally never felt it. The awesome beauty of my home state never ceases to amaze me, and I always miss it enormously when I travel.
For years, Guam would be the butt of jokes in the United States as an uninviting place, where boredom led to "rock fever," a cranky longing to get off the island.