This can be determined by measuring the amount of carboxyhemoglobin compared to the amount of hemoglobin in the blood.The ratio of carboxyhemoglobin to hemoglobin molecules in an average person may be up to 5%, although cigarette smokers who smoke two packs per day may have levels up to 9%. In symptomatic poisoned people they are often in the 10–30% range, while persons who die may have postmortem blood levels of 30–90%.As people may continue to experience significant symptoms of CO poisoning long after their blood carboxyhemoglobin concentration has returned to normal, presenting to examination with a normal carboxyhemoglobin level (which may happen in late states of poisoning) does not rule out poisoning. Measuring
Carbon monoxide may be quantitated in blood using spectrophotometric methods or chromatographic techniques in order to confirm a diagnosis of poisoning in a person or to assist in the forensic investigation of a case of fatal exposure. A CO-oximeter can be used to determine carboxyhemoglobin levels. Pulse CO-oximeters estimate carboxyhemoglobin with a non-invasive finger clip similar to a pulse oximeter. These devices function by passing various wavelengths of light through the fingertip and measuring the light absorption of the different types of hemoglobin in the capillaries. The use of a regular pulse oximeter is not effective in the diagnosis of carbon monoxide poisoning as these devices may be unable to distinguish carboxyhemoglobin from oxyhemoglobin.Breath CO monitoring offers an alternative to pulse CO-oximetry. Carboxyhemoglobin levels have been shown to have a strong correlation with breath CO concentration.
Methyldopa, sold under the brand name Aldomet among others, is a medication used for high blood pressure. It is one of the preferred treatments for high blood pressure in pregnancy. For other types of high blood pressure including very high blood pressure resulting in symptoms other medications are typically preferred. It can be given by mouth or injection into a vein. Onset of effects is around 5 hours and they last about a day.Common side effects include sleepiness. More severe side effects include red blood cell breakdown, liver problems, and allergic reactions. Methyldopa is in the alpha-2 adrenergic receptor agonist family of medication. It works by stimulating the brain to decrease the activity of the sympathetic nervous system.Methyldopa was discovered in 1960. It is on the World Health Organizations List of Essential Medicines. Medical uses
Methyldopa is used in the clinical treatment of the following disorders:

Hypertension (or high blood pressure)
Gestational hypertension (or pregnancy-induced hypertension) and pre-eclampsia. Side effects
Methyldopa is capable of inducing a number of adverse side effects, which range from mild to severe. Nevertheless, they are generally mild when the dose is less than 1 gram per day.