There are no good reasons for a physician in the US to refuse to prescribe oxygen therapy for acute cluster headaches when they tend prescribe far more invasive medications like verapamil as a preventative or imitrex as an abortive. These medications are very expensive and both have a long list of side effects. The same is not true for oxygen therapy... Oxygen can also be combined with other cluster headache medications. There are no real side effects if oxygen therapy is used properly. See the following links:
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Google the following between the brackets and look at the number of Hits:
["Cluster Headache" Verapamil "Side Effects] - about 24,800
["Cluster Headache" Imitrex "Side Effects"] - about 21,700
["Cluster Headache" oxygen Therapy Inhalation "Side Effects"] - about 2,210
The raw numbers of hits are proof enough until you peruse a few of the hits in each of these Internet queries where you'll see the safety of oxygen therapy over the other invasive medications is even greater. In general, Verapamil and Imitrex have several potentially harmful side effects where oxygen therapy is virtually free of side effects.
Yes there is a side effect of oxygen therapy called pulmonary oxygen toxicity, but you would need to breathe 100% oxygen continuously for 12 hours without breathing normal air for the symptoms of this condition to appear. Even then, these symptoms clear rapidly with no lasting effects by breathing normal air.
Moreover, at a flow rate of 8 liters/minute, 12 hours of constant would require 2 full M-size or 11 E-size oxygen cylinders ganged to a single manifold. The risk of pulmonary oxygen toxicity after 15 to 20 minutes of oxygen therapy is extremely low to non-existent.
Oxygen therapy is the least expensive abortive at around $1.50 per abort and as the Google queries above illustrate, there are no real or lasting side effects save for an occasional dry mouth or nose when it's used to abort cluster headache attacks.
Inhalation of 100% oxygen is so safe Navy and Marine Corps pilots flying $30 Million dollar tactical jet aircraft are required to breathe 100% oxygen on all flights from takeoff to touch down. The average mission length for these flights is over 2 hours and speaking from experience, the flow rates are well above 15 liters/minute.
Navy and Marine Corps pilots have been breathing 100% oxygen in tactical aircraft for over 60 years and the number of pilots over that time comes to several hundred thousand. There are no documented cases of any health problems attributed to breathing 100% oxygen and these aviators all receive annual flight physical examinations. That's kind of like the largest open label clinical study in history...
The way I see it Cluster Headache sufferers here in the US have an implied Patient's Bill of Rights. These include the right to ask and receive answers to the following questions from your primary care physician or neurologist if you've been diagnosed with episodic or chronic cluster headaches:
1. How many cluster headache sufferers have you treated?
2. How many cluster headache sufferers have you treated in the last year?
3. What are the most effective preventative medications you prescribe for cluster headaches? What are the side effects of these preventative medications?
4. What are the most effective abortive medications you prescribe for cluster headaches? What are the side effects of these abortive medications?
3. Do you prescribe oxygen therapy as an abortive for cluster headaches? What are the potential side effects? (You should already know the answer.)
Note: In countries practicing socialized medicine like Sweden, your neurologist can suggest oxygen therapy, but you'll need to see a pulmonologist for the prescription... watch out for universal healthcare... it's going to be just as bad...
4. If your physician or neurologist refuses to prescribe oxygen therapy as an abortive for cluster headaches, ask for the rationale.
Remember... One way or another, you're paying for the medical care the physician is providing, the medications, and it's your body. Be polite, but also share your concerns over potentially harmful side effects of any medication. If the responses to the questions above sound reasonable you may be able to work out a prescription for the oxygen therapy.
Take care,
V/R, Batch