HEADACHE different causes

1. Headaches can arise from many different causes.
 In the first few days of flight, headward fluid shift and Space Motion Sickness may lead to headaches, which typically is resolved with simple treatment and adaptation to weightlessness. Other potential causes include tension (chronic contraction of scalp
muscles), eye strain (especially associated with dimly lit areas), chronic noise exposure, dental disorders, respiratory illness and fever, and sided effects from certain drugs such as cardiac medications. Commonly, headaches associated with space flight are simple and self-limited, and usually treated with mild to moderate strength pain medications. If there are any other associated warning symptoms such as vision changes, ringing in ears, nausea and vomiting (aside from Space Motion Sickness), personality changes, neck stiffness, light sensitivity, or headache becomes severe or more frequent, schedule a PMC and contact
Surgeon immediately.

2. Environmental factors
must be considered as a cause of headaches. These include toxicity from such agents as carbon monoxide and other combustion products, hypoxia, carbon dioxide toxicity, and chronic noise exposure. It is vital that if more than one crewmember develops a headache at the same time, that the atmosphere be sampled with the Compound Specific Analyzer for Combustion Products (CSA-CP) and the portable Carbon Dioxide Monitor. Also, if headaches develop in a certain region of the ISS, these gas analysis readings must be
obtained in that region. Surgeon will advise if achieved gas samples are indicated. Headaches occurring at night in a sleep station or other more enclosed area is possibly due to local CO2 buildup; if possible, try to increase ventilation to this area.