Symptoms associated with the absorption of COHb37
| COHb concentration | Effects |
|---|---|
| 0.0%–2.5% | No apparent symptoms |
| 2.5%–5.0% | Altered vision |
| Arterial dilation | |
| Reduced attention span particularly while driving an automobile | |
| 5.0%–10% | Altered brightness sensitivity |
| Unusual increase in strained breathlessness | |
| Distortion of fine manual dexterity | |
| 20%–30% | Headaches |
| Start of nausea | |
| Coordination problems | |
| 30%–40% | Severe headaches |
| Dizziness | |
| Nausea and vomiting | |
| Judgement alteration | |
| 40%–50% | Aggravation of the same symptoms |
| Confusion | |
| 50%–60% | Loss of consciousness |
| Convulsions | |
| >60% | Coma |
| Respiratory arrest | |
| Death |