عقرب ها هنگام فشار دادن یا دست زدن، نیش های دردناکی ایجاد می کنند. بیشتر گونه های مهم پزشکی به خانواده Buthidae تعلق دارند. مسمومیت سیستمیک توسط اعضایی از جنس Centruroides (که در منطقه جنوب غربی ایالات متحده و در مکزیک یافت می شود) ؛ تیتیوس Tityus (در برزیل و ترینیداد)؛ Androctonus، Buthus، Leiurus و Nebo (در شمال آفریقا و خاورمیانه و خاورنزدیک) ؛ همیسکوپیوس Hemiscorpius (در ایران، عراق و بلوچستان)؛ Parabuthus (در آفریقای جنوبی)؛ و مزوبوتوس (در شبه قاره هند) ایجاد می شود. عقرب‌ها بندپایان شب‌زی هستند که در خانه‌ها یا نزدیک آن‌ها زندگی می‌کنند، بیشتر برخوردهای بین این حیوانات و انسان ها در این مکان ها اتفاق می افتد. مسافران هنگامی که به طور تصادفی عقرب هایی را که در رختخواب ها، چمدان ها، کفش ها و لباس ها پنهان شده اند را لمس می کنند، مورد گزش قرار می گیرند.

تظاهرات بالینی عقرب‏ گزیدگی

مسمومیت موضعی باعث درد، اریتم و تورم می شود. مسمومیت سیستمیک معمولاً در 2 مرحله ایجاد می شود: مرحله کولینرژیک شامل استفراغ، تعریق، ترشح بیش از حد بزاق، پریاپیسم، برادی کاردی و افت فشار خون شریانی و به دنبال آن مرحله آدرنرژیک شامل افزایش فشار خون شریانی، تاکی کاردی و نارسایی قلبی. اعصاب جمجمه و اتصالات عصبی عضلانی نیز ممکن است تحت تأثیر قرار گیرند. نارسایی تنفسی می تواند ناگهانی باشد و چند عاملی است، از جمله ترشح بیش از حد برونش.

پیشگیری و کمک های اولیه

چک کردن کفش، لباس، چمدان و تخت برای یافتن عقرب‌ مهم‌ترین اقدام پیشگیرانه فردی است. درزگیری سوراخ‌ها و شکاف‌های دیوار خانه‌ها باعث کاهش مخفیگاه‌ها می‌شود.

مدیریت بالینی

درد موضعی با بی حسی موضعی و بی حسی منطقه ای کنترل می شود. مدیریت زخم و پیشگیری از کزاز مهم است. کنترل اثرات بر سیستم عصبی خودمختار  و تحریک بیش از آن با آلفا بلوکرها (به عنوان مثال، پرازوسین)، مسدود کننده های کانال کلسیم (مانند نیفدیپین) و مهارکننده های ACE (مانند کاپتوپریل) با موفقیت در اسرائیل و هند انجام شده است.خوش بختانه آنتی ونوم عقرب در ایران موجود است.

• Hottentotta (formerly Mesobuthus) species – We recommend that patients stung by Hottentotta (formerly Mesobuthus) species who demonstrate signs of Grade II or higher scorpion envenomation receive intravenous (IV) scorpionspecific antivenom . Antivenom should be given as soon as possible after the sting, ideally within four hours, because it is less effective once the venom is fully absorbed. Small trials performed in patients with systemic scorpion envenomation treated in India and the United States show that equine-derived F(ab’)2 scorpion-specific antivenom significantly shortens the duration of systemic toxicity . For patients with Grade II envenomation after stings by Hottentotta (formerly Mesobuthus) species, it also significantly decreases the amount of medication required to control hypertension and prevents progression to cardiotoxicity . In one trial, pediatric patients who received antivenom required, on average, a total of two doses of prazosin compared to four doses in patients who received prazosin alone . In India, the routine use of antivenom and prazosin combined with improved intensive care measures has been associated with a significant decrease in mortality from 26 percent in 1961 to <1 percent in 2012.
• Androctonus or Buthus species – Evidence does not support administration of scorpion-specific antivenom to patients with Grade II or higher envenomation after stings by Androctonus or Buthus species given the low likelihood of death
  and the potential for adverse effects from the antivenom . Nevertheless, because high quality evidence is lacking, some regional experts still support its use.
  Observational studies and one trial of scorpion antivenom for stings by Androctonus and Buthus species have failed to show a benefit of scorpion-specific antivenom over supportive care alone . However, these studies were performed over 10 to 20 years ago and have significant methodologic flaws (eg, lack of blinding, baseline differences in severity of illness prior to antivenom administration between groups, and/or lack of controlling for the time between reported sting and antivenom administration)
• Dosing and administration — Clinicians should follow the guidance of experts in their regions and manufacturer instructions when determining the dose of antivenom. The dose of antivenom varies by species and is also based upon the estimated amount of venom delivered during the sting and the severity of envenomation. Antivenom dosing is not based upon the patient’s weight and should not be reduced in children. Scorpion antivenom should be given IV.

Prior to the administration of antivenom, medications and equipment for the treatment of anaphylaxis should be immediately available, including IV fluids, epinephrine, and intubation equipment. Whenever possible, antivenom should be administered in settings capable of emergency or intensive care. Allergic reactions should be managed by immediately stopping IV infusion of the antivenom (if applicable) and treating symptoms appropriately ) . All patients receiving antivenom should be informed of the possibility of serum sickness and the symptoms suggestive of serum sickness (eg, fever, rash, arthralgias, and arthritis) and advised to seek medical care if such symptoms occur.

• Prazosin
  — For patients with Grade II or higher scorpion envenomation caused by Hottentotta (formerly Mesobuthus) species, we recommend prazosin in addition to scorpion-specific antivenom rather than antivenom alone. Prazosin has been shown to mitigate excessive catecholamine release and progression to cardiotoxicity . For patients with Grade II or higher scorpion envenomation caused by Androctonus, Buthus, Leiurus, or Tityus species, we suggest treatment with prazosin. The recommended prazosin dose for scorpion envenomation is 0.5 mg (30 micrograms/kg, maximum dose 0.5 mg in pediatric patients) orally or via gastric tube every three hours until systemic toxicity resolves.
• Supportive care
  — All patients with Grade II or higher scorpion envenomations should be admitted to a unit capable of providing intensive supportive care. Clinicians should anticipate the need to treat autonomic dysfunction (“autonomic storm”),cardiotoxicity, and pancreatitis.
• Autonomic dysfunction (autonomic storm)
  — Supportive treatment of autonomic stimulation and its complications after scorpion envenomation is provided and discussed below.
  ●Parasympathetic toxicity – — Soon after scorpion envenomation, patients may require frequent oral suctioning for excessive salivation and administration of oxygen and/or inhaled albuterol to treat bronchorrhea and bronchospasm.
  Administration of subcutaneous epinephrine for bronchospasm should be avoided because it may enhance sympathetic toxicity.
  Atropine may also potentiate sympathomimetic effects after envenomation and should be avoided unless patients develop severe bradycardia (bradycardia with hypotension and/or somnolence) or third degree atrioventricular block .
  Vomiting may be treated with antiemetics (eg, metoclopramide or, if no hypocalcemia or prolonged QTc on electrocardiogram [EKG], ondansetron). Fluid losses should be replaced with IV isotonic fluids (eg, normal saline or buffered isotonic solutions such as Ringer’s lactate). The clinician should avoid fluid overload which may exacerbate heart failure in patients with sympathetic toxicity.
  ●Sympathetic toxicity – — Prazosin, a post-ganglionic alpha1-adrenergic receptor blocker counteracts excessive catecholamine release and is the primary treatment for sympathetic storm in conjunction with antivenom. Prazosin has also been shown to decrease the risk of progression to cardiotoxicity.
  ●Heart failure – — Heart failure after scorpion envenomation is caused by excessive circulating catecholamines. The resulting left ventricular dysfunction with reduced ejection fraction can be rapidly reversed with proper treatment.
  Prazosin, a post-ganglionic alpha1-adrenergic receptor blocker that counteracts excessive catecholamine release and, through its action as a vasodilator, provides treatment for heart failure and acute pulmonary edema is associated with reduced duration of cardiotoxicity when given in conjunction with antivenom . Continuous IV infusion of nitroglycerin and a combination of dobutamine and nitroglycerin have also been used successfully to treat pulmonary edema and decompensated shock in critically ill patients .
  Stabilization of patients also encompasses general treatment of acute decompensated heart failure with reduced left ventricular function/ejection fraction .
• Acute pulmonary edema – Patients with tachypnea and signs of pulmonary edema should receive supplemental oxygen, assisted ventilation (eg, noninvasive or mechanical ventilation) as needed for respiratory failure, and diuretics.
• Hypotension Patients who develop persistent cardiogenic shock despite treatment with antivenom and prazosin warrant vasopressor support and afterload reduction. In small case series, dobutamine, at a continuous infusion of 5 to 20 micrograms/kg/minute, has successfully reversed severe heart failure after scorpion envenomation and is most commonly used. Patients with refractory heart failure with hypotension and pulmonary edema despite dobutamine therapy may benefit from a carefully titrated nitroglycerin infusion (starting dose: 0.5 micrograms/kg/minute; if no response, increase the infusion by 50 percent every 15 minutes as needed up to a maximum dose of 5 micrograms/kg/minute)

Unlike prazosin, other vasodilators, such as hydralazine or nifedipine, cause reflex sympathetic stimulation which may compound excessive catecholamine release after a scorpion sting and should be avoided

• Tachyarrhythmias – — Tachyarrhythmias after scorpion envenomation typically arise from catecholamine-induced myocarditis, myocardial ischemia, or both . Electrolyte disturbances (eg, hyperkalemia or hypocalcemia) have alsobeen described.
  In addition to emergency administration of scorpion-specific antivenom, these arrhythmias should be treated according to the principles of advanced cardiac life support (ACLS) and pediatric advanced life support (PALS) .
  Although evidence is lacking, amiodarone may have a theoretical advantage over lidocaine for treating patients with ventricular arrhythmias after scorpion stings because of its sympatholytic effects
• Pancreatitis
  — Pancreatitis after scorpion envenomation is typically transient, lasting one to two days and responds to supportive care including pain control, no oral intake except medications until pain is resolving, regular monitoring of blood glucose with insulin administration for hyperglycemia, and monitoring of electrolytes and calcium. Fluid replacement should be done carefully in patients with co-existent heart failure. Pancreatic necrosis or pseudocyst are uncommon but should be sought as the
  etiology of persistent abdominal pain with vomiting
• Delirium and other neurologic complications – — Benzodiazepines (eg, midazolam or diazepam) can help manage delirium and are also indicated for the initial treatment of seizures in conjunction with appropriate stabilization and treatment of underlying causes such as hypoxemia, hypotension, and hypoglycemia.