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Carbon Dioxide Toxicity
A dull throbbing head pain after diving is usually a symptom of a headache caused by carbon dioxide toxicity. This type of headache is common to divers and is caused by a build up of carbon dioxide in the body. This increase in waste gas is usually due to hypoventilation (too little air intake). Hypoventilation usually happens because a scuba diver doesnt take large enough breaths from his or her air tank or doesnt breathe often enough. Simply put, not breathing enough to get rid of the carbon dioxide created in the body will lead to a build up and cause a headache. The best treatment for this type of headache is to take slow, deep breaths to reduce the build up. Carbon dioxide headaches dont respond well to pain relievers.
DCS Headache
Headaches can also be a sign of decompression sickness (DCS). DCS is caused by the formation of bubbles as dissolved nitrogen comes out of the tissues on ascent. DCS can lead to permanent physical impairment or death. Seek immediate medical attention if a diver complains of a headache and has other signs of DCS: joint pain, swelling, skin rash, itching, dizziness, nausea, vomiting, ringing in the ears, and extreme exhaustion. A scuba diver is at risk of DCS when he or she does not decompress after long or deep dives, before surfacing, or when he or she ascends too quickly or makes a panic ascent.
Things you can do to help prevent headaches and enjoy your dive are: loosen your mask strap to avoid excess pressure, relax during the dive, take slow deep breaths, avoid caffeine and tobacco, perform a safety stop before surfacing, practice safe diving, and wear sufficient thermal protection.
