Methane gas poisoning symptoms can range from mild to severe. Inhaling methane may cause dizziness, headaches, nausea, and fatigue in the short term. Prolonged exposure can lead to more severe symptoms, including chest pain, difficulty breathing, and confusion. In extreme cases, unconsciousness and death can occur. If you suspect methane gas exposure, seek fresh air immediately, and if symptoms persist or worsen, seek medical attention promptly. Preventative measures such as proper ventilation and gas detectors can help mitigate the risks associated with methane gas poisoning.