PSA: Be careful about doing McKenzie technique exercises! It made it worse for me because the physical therapist didn't do a good enough analysis! I encourage a thorough assessment that includes an MRI review of your spine first.

The link posted above mentions it as well

> Although most patients favor spinal extension, there are, however, patients who favor spinal flexion instead. For these types of patients, the repetitive extension based exercises can possibly lead to peripheralization which is the worsening of distal referred pain from repetitive motion. In contrast to centralization, peripheralization does not carry a good prognosis and is to be avoided. It is thus vital for clinicians to form an accurate assessment of the directional preference rather than assuming a patient will favor extension and thereby proceeding with therapy based on that assumption.

EDIT: Just to clarify further, the potential side effects are not just "pain". In my case, doing a cobra pose causes me to piss myself and lose feeling in my legs. This can be catastrophic to some people. Please folks, do not just go off some rando on social media telling you "X will treat your neck/back pain!". You can end up seriously much worse than you started. You need to SEE what the problem is first and only an MRI and a trained physician can tell you what is appropriate for you.