Symptoms of paraquat poisoning

I believe that everyone is relatively unfamiliar with paraquat. In fact, paraquat is a herbicide. Paraquat is very toxic, so we must avoid accidental ingestion or taking paraquat on our own initiative. We need to learn more about paraquat and know what symptoms will appear if we accidentally take paraquat. Once we show symptoms of paraquat poisoning, we must know how to deal with it.

Paraquat poisoning is very difficult to treat. We do not have a good emergency medicine for paraquat, so once paraquat poisoning occurs, in addition to using vomiting, washing and other methods to block the absorption of the poison, we can also use blood purification to promote the excretion of the poison.

Paraquat (PQ), also known as Paraquat and Gramoxone, is a highly effective non-selective contact herbicide that is highly toxic to humans and animals. Accidental ingestion or self-ingestion can cause acute poisoning and has become a common cause of death from pesticide poisoning. The lethal dose for adults is 5-15 ml of 20% aqueous solution (20-40 mg/kg). Paraquat is absorbed through the digestive tract, skin, and respiratory tract. Its toxicity affects multiple organs throughout the body. In severe cases, it can lead to multiple organ dysfunction syndrome (MODS). The lungs are the main target organ, which can cause "paraquat lung", with early manifestations of acute lung injury (ALI) or acute respiratory distress syndrome (ARDS), and later on, alveolar and interstitial fibrosis. It is the main cause of death from paraquat poisoning, with a mortality rate of 50% to 70%.

Paraquat poisoning is commonly seen in clinical practice as a result of self-ingestion or accidental ingestion and is absorbed through the digestive tract; injection is extremely rare. Intact skin can effectively prevent the absorption of paraquat, but long-term contact, contaminated scrotum or perineum, or large-scale contact with damaged skin may still cause systemic toxicity.

1. Oral poisoning

There are burning sensation in the mouth, erosion and ulcers of the oral and esophageal mucosa, nausea, vomiting, abdominal pain, diarrhea, and even vomiting and bloody stools. In severe cases, complications such as gastric perforation and pancreatitis occur. Some patients experience liver enlargement, jaundice, abnormal liver function, and even liver failure. Patients may experience dizziness and headache, and a few may develop central nervous system symptoms such as hallucinations, fear, convulsions, and coma. Renal damage is the most common symptom, manifested as hematuria, proteinuria, oliguria, increased blood BUN and Cr, and in severe cases, acute renal failure. Lung damage is the most prominent and severe, manifested by cough, chest tightness, shortness of breath, cyanosis, and dyspnea. Physical examination may reveal decreased breath sounds and dry and wet rales in both lungs. Those who take large amounts orally will experience pulmonary edema and pulmonary hemorrhage within 24 hours, and often die from ARDS within a few days; those who do not take large amounts will present a subacute course, with chest tightness and shortness of breath occurring in about a week, and dyspnea reaching a peak in 2 to 3 weeks, and patients often die from respiratory failure. A small number of patients developed complications such as pneumothorax, mediastinal emphysema, toxic myocarditis, and pericardial hemorrhage.

2. Local contact with paraquat poisoning

The clinical manifestations are contact dermatitis and chemical burns of mucous membranes, such as skin erythema, blisters, ulcers, etc., burns of the conjunctiva and cornea forming ulcers and even perforations. Prolonged and excessive exposure may cause systemic damage or even be life-threatening.

3. Those who are exposed to paraquat through injection (blood vessels, muscles, skin, etc.)

Exposure to paraquat through injection (blood vessels, muscles, skin, etc.) is rare, but the clinical manifestations are severe and the prognosis is poor.

Above we introduced what paraquat is. We know that paraquat is a herbicide. Once paraquat is taken by mistake or by self-administration, it can easily cause poisoning. Moreover, paraquat poisoning is very difficult to treat, so we need to understand some knowledge about paraquat poisoning. The above article introduces the symptoms of paraquat poisoning in detail.