I would like to know if cluster headaches can suddenly switch from one side to another; for 30+ years I've endured with them and they've always been on the left side until now and while I'm not sure (yet) if they are true cluster, I need to know of this is possible/has happened in the past.
Thank you!

Yes, it does happen.

J Headache Pain. 2009 Aug;10(4):259-63. Epub 2009 Jun 3.
Lateralization in cluster headache: a Nordic multicenter study.

Meyer EL, Laurell K, Artto V, Bendtsen L, Linde M, Kallela M, Tronvik E, Zwart JA, Jensen RM, Hagen K.

Department of Clinical Neuroscience, Division of Neurology at Karolinska Insitutet, Stockholm, Sweden.

A slight predominance of cluster pain on the right side has been reported in several studies. The aim of this large retrospective Nordic multicenter study was to estimate the prevalence of right- and left-sided pain in cluster headache (CH) patients with side-locked pain, the prevalence of side shifts in episodic and chronic CH patients, and the occurrence of cranial autonomic symptoms related to pain side.

AMONG 383 CLUSTER PATIENTS, 55 (14%) HAD EXPERIENCED PAIN SIDE SHIFT. OF THE REMAINING 328 INDIVIDUALS WITHOUT SIDE SHIFT, THERE WAS NO SIGNIFICANT DIFFERENCE BETWEEN THE OCCURRENCE OF RIGHT-SIDED AND LEFT-SIDED PAIN (54 VS. 46%). THE PREVALENCE OF SIDE SHIFT WAS SIMILAR FOR EPISODIC AND CHRONIC CH AND THE OCCURRENCE OF CRANIAL AUTONOMIC SYMPTOMS WAS NOT INFLUENCED BY THE PAIN SIDE. In conclusion, previous reports of a side difference in location of cluster pain could not be confirmed in this large Nordic sample.

Publication Types:
Research Support, Non-U.S. Gov't

PMID: 19495933 [PubMed]

As you've been told, the answer is "yes." I'm not sure why it would matter to me, but there's something famiiar with the "same side always" attacks. I guess it's because I know how to sort out the various warnings and such and I think if I became a switch hitter, I'd have less warning. Or something equally irrational. blessings. lance

35 years and they haven't switched sides for me....yet! Yeah it does happen, I've seen a number of people post on the board. Some switch from cycle to cycle, some even switch during a cycle.

Joe

My cycle typically ends on one sides, only to give a few days pain-free, and then to start a new cycle on the other side.