Breathing training for treating panic disorder. Useful intervention or impediment?

Carr et al. (2003) read every breathing-training paper they could find on panic disorder. They did not run new patients; they judged the old experiments. Their goal was to see if slow-breathing lessons really calm panic or make it worse.

They found most studies had no CO₂ meters, no control groups, and no long-term checks. Because of these holes, they called the evidence 'inconclusive.'

The review says we still do not know if breathing training helps or hurts panic patients. The old studies mix different techniques, different lengths, and different ways of scoring panic. Without better data, clinicians are flying blind.

Two years earlier the same research group published a small case-series, Meuret et al. (2001), that looked very positive. Four adults used a handheld CO₂ meter at home. After one month their panic dropped and their CO₂ levels rose toward normal. That study is exactly the kind the 2003 review says is missing.

Phillips et al. (2019) tried diaphragmatic breathing with three children who hit peers to escape tasks. Only one child improved; the other two needed extra reinforcement plans. The mixed result backs the review’s warning that breathing alone is not a sure fix.

Gabriely et al. (2020) compared device-guided breathing against mindfulness in college students with ADHD. Breathing lowered stress a little, but mindfulness beat it on attention scores. Again, breathing showed modest effects, matching the 'inconclusive' label.

If you treat adults with panic disorder, do not throw out breathing drills yet. Add a cheap portable CO₂ meter to see if the client really raises end-tidal CO₂. Track panic frequency and CO₂ together for four weeks. If both improve, keep going; if not, pivot to exposure or reinforcement-based strategies. This simple check turns an unclear technique into data-driven treatment.