Use of antivenom for severe spider bites may be indicated, especially in the case of neurotoxic venoms. Effective antivenoms exist for "Latrodectus", "Atrax", and "Phoneutria" venom. Antivenom in the United States is in intravenous form but is rarely used, as anaphylactic reaction to the antivenom has resulted in deaths. In Australia, antivenom in intramuscular form was once commonly used, but use has declined. In 2014 some doubt as to antivenom effectiveness has been raised. In South America an antivenom is available for "Loxosceles" bites, and it appears antivenom may be the most promising therapy four recluse bites. However, in experimental trials recluse antivenom is more effective when given early, and patients often do not present for 24 or more hours after envenomation, possibly limiting the effect of such intervention.

Efforts to prevent bites include clearing clutter and the use of pesticides.

OSHA recommends that workers take following measures to prevent spider bite:

- Wear a long-sleeved shirt, hat, gloves, and boots when handling boxes, firewood, lumber, rocks, etc.

- Inspect and shake out clothing and shoes before getting dressed.

- Use insect repellents, such as DEET or Picaridin, on clothing and footwear.

Snakebite first aid recommendations vary, in part because different snakes have different types of venom. Some have little local effect, but life-threatening systemic effects, in which case containing the venom in the region of the bite by pressure immobilization is desirable. Other venoms instigate localized tissue damage around the bitten area, and immobilization may increase the severity of the damage in this area, but also reduce the total area affected; whether this trade-off is desirable remains a point of controversy. Because snakes vary from one country to another, first aid methods also vary.

Many organizations, including the American Medical Association and American Red Cross, recommend washing the bite with soap and water. Australian recommendations for snake bite treatment recommend against cleaning the wound. Traces of venom left on the skin/bandages from the strike can be used in combination with a snake bite identification kit to identify the species of snake. This speeds determination of which antivenom to administer in the emergency room.

Snakes are most likely to bite when they feel threatened, are startled, are provoked, or when they have been cornered.

Snakes are likely to approach residential areas when attracted by prey, such as rodents. Regular pest control can reduce the threat of snakes considerably. It is beneficial to know the species of snake that are common in local areas, or while travelling or hiking. Africa, Australia, the Neotropics, and southern Asia in particular are populated by many dangerous species of snake. Being aware of—and ultimately avoiding—areas known to be heavily populated by dangerous snakes is strongly recommended.

When in the wilderness, treading heavily creates ground vibrations and noise, which will often cause snakes to flee from the area. However, this generally only applies to vipers, as some larger and more aggressive snakes in other parts of the world, such as mambas and cobras, will respond more aggressively. When dealing with direct encounters it is best to remain silent and motionless. If the snake has not yet fled it is important to step away slowly and cautiously.

The use of a flashlight when engaged in camping activities, such as gathering firewood at night, can be helpful. Snakes may also be unusually active during especially warm nights when ambient temperatures exceed . It is advised not to reach blindly into hollow logs, flip over large rocks, and enter old cabins or other potential snake hiding-places. When rock climbing, it is not safe to grab ledges or crevices without examining them first, as snakes are cold-blooded and often sunbathe atop rock ledges.

In the United States, more than 40 percent of people bitten by snake intentionally put themselves in harm's way by attempting to capture wild snakes or by carelessly handling their dangerous pets—40 percent of that number had a blood alcohol level of 0.1 percent or more.

It is also important to avoid snakes that appear to be dead, as some species will actually roll over on their backs and stick out their tongue to fool potential threats. A snake's detached head can immediately act by reflex and potentially bite. The induced bite can be just as severe as that of a live snake.

Dead snakes are also incapable of regulating the venom they inject, so a bite from a dead snake can often contain large amounts of venom.

People who have been bitten by a black widow spider are recommended to seek professional medical assistance for symptoms. Symptoms self-resolve in hours to days in a majority of bites without medical intervention.

Medical treatments have varied over the years. Some treatments (e.g. calcium gluconate) have been discovered to be useless. Currently, treatment usually involves symptomatic therapy with pain medication, muscle relaxants, and antivenom. When the pain becomes unbearable, antivenom is administered. Antivenom historically completely resolves pain in a short time. Antivenom is made by injecting horses with latrodectus venom over a period of time. The horse develops antibodies against the venom. The horse is bled and the antibodies purified for later use. Doctors recommend the use of anti-inflammatory medications before antivenom administration, because antivenom can induce allergic reactions to the horse proteins. The efficacy of antivenom has come under scrutiny as patients receiving placebo have also recovered quickly.

Antivenom is used widely in Australia for redback bites; however, in the United States it is less commonly used. Antivenom made from prior spider bite victims has been used since the 1920s. Opiates such as morphine relieve pain and benzodiazepines ease muscle spasm in most patients.

The vast majority of victims fully recover without significant lasting problems (sequelae). Death from latrodectism is reported as high as 5% to as low as 0.2%. In the United States, where antivenom is rarely used, there have been no deaths reported for decades.

Despite frequent reference to youth and old age being a predisposing factor it has been demonstrated that young children appear to be at lowest risk for a serious bite, perhaps owing to the rapid use of antivenom. Bite victims who are very young, old, hypotensive, pregnant or who have existing heart problems are reported to be the most likely to suffer complications. However, due to the low incidence of complications these generalizations simply refer to special complications (see Special circumstances).

Cat bites can often be prevented by:

- instructing children not to tease cats or other pets.

- being cautious with unfamiliar cats.

- approaching cats with care, even if they appear to be friendly.

- avoiding rough play with cats and kittens.

Rough play causes is perceived as aggressive. This will lead to the cat being defensive when approached by people. Preventing cat bites includes not provoking the cat.

Anti-venoms are commercially prepared antibodies to toxins in animal bites. They are specific for each bite. There are several anti-venoms commercially available in Brazil, which have been shown to be effective in controlling the spread of necrosis in rabbits. When administered immediately, they can almost entirely neutralize any ill effects. If too much time is allowed to pass, the treatment becomes ineffective. Most victims do not seek medical attention within the first twelve hours of being bitten, and these anti-venoms are largely ineffective after this point. Because of this, anti-venoms are not being developed more widely. They have, however, been proven to be very effective if administered in a timely manner and could be utilized in Brazil as a legitimate technique.

Despite being one of the few medically important spider bites, there is no established treatment for the bite of a Loxosceles spider. Physicians wait for the body to heal itself, and assist with cosmetic appearance. There are, however, some remedies currently being researched.

The first step in treatment includes washing and then irrigating the bite wound.

Seek medical attention if: if the cat has not been vaccinated against rabies.

A tetanous booster is given to the person if It has been more than 5 years since their last tetanus shot. If a cat has bitten someone, and there is no evidence that the cat has been vaccinated against rabies, the person will be treated for rabies infection.

An escharotic is a substance that causes tissue to die and slough off. Examples include acids, alkalis, carbon dioxide, metallic salts and sanguinarine, as well as certain medicines like imiquimod. Escharotics known as black salves, containing ingredients such as zinc chloride and sanguinarine containing bloodroot extracts, were traditionally used in herbal medicine as topical treatments for localised skin cancers, but often cause scarring and can potentially cause serious injury and disfigurement. Consequently, escharotic salves are very strictly regulated in most western countries and while some prescription medicines are available with this effect, unauthorized sales are illegal. Some prosecutions have been pursued over unlicensed sales of escharotic products such as Cansema.

Treatment requires keeping the person from being repeatedly bitten and possible symptomatic use of antihistamines and corticosteroids (either topically or systemically). There however is no evidence that medications improve outcomes and symptoms usually resolve without treatment in 1–2 weeks.

Avoiding repeated bites can be difficult, since it usually requires eradicating bed bugs from a home or workplace; eradication frequently requires a combination of pesticide and non pesticide approaches. Pesticides that have historically been found to be effective include pyrethroids, dichlorvos and malathion. Resistance to pesticides has increased significantly over time and there are concerns of negative health effects from their usage. Mechanical approaches such as vacuuming up the insects and heat treating or wrapping mattresses have been recommended.

Many species of arthropods (insects, arachnids and others) regularly or occasionally bite or sting human beings. Insect saliva contains anticoagulants and enzymes that cause local irritation and allergic reactions. Insect venoms can be delivered by their stingers, which often are modified ovipositors, or by their mouthparts. Insect, spider and scorpion venom can cause serious injury or death. Dipterans account for the majority of insect bites, while hymenopterans account for the majority of stings. Among arachnids spider bites are the most common. Arthropods bite or sting humans for a number of reasons including feeding or defense. Arthropods are major vectors of human disease, with the pathogens typically transmitted by bites.

Bed bug bites are caused by bed bugs primarily of two species "Cimex lectularius" (the common bed bug) and "Cimex hemipterus". Infestation is rarely due to a lack of hygiene. These insects feed exclusively on blood and may survive a year without eating. They are attracted by body warmth and carbon dioxide. Transfer to new places is usually in the personal effects of the human they feed upon.

Dwellings can become infested with bed bugs in a variety of ways, such as:

- Bugs and eggs inadvertently brought in from other infested dwellings on a visiting person's clothing or luggage;

- Infested items (such as furniture especially beds or couches, clothing, or backpacks) brought in a home or business;

- Nearby dwellings or infested items, if easy routes are available for travel, e.g. through ducts or false ceilings;

- Wild animals (such as bats or birds) that may also harbour bed bugs or related species such as the bat bug;

- People visiting an infested area (e.g. dwelling, means of transport, entertainment venue, or lodging) and carrying the bugs to another area on their clothing, luggage, or bodies. Bedbugs are increasingly found in air travel.

- Though bed bugs will feed on pets, they do not live or travel on the skin of their hosts, and pets are not believed a factor in their spread.

Chiggers are commonly found on the tip of blades of grasses to catch a host, so keeping grass short, and removing brush and wood debris where potential mite hosts may live, can limit their impact on an area. Sunlight that penetrates the grass will make the lawn drier and make it less favorable for chigger survival.

Chiggers seem to affect warm covered areas of the body more than drier areas. Thus, the bites are often clustered behind the knees, or beneath tight undergarments such as socks, underwear, or brassieres. Areas higher in the body (chest, back, waist-band, and under-arms) are affected more easily in small children than in adults, since children are shorter and are more likely than adults to come in contact with low-lying vegetation and dry grass where chiggers thrive. An exceptional case has been described in the eye, producing conjunctivitis.

Application of repellent to the shoes, lower trousers and skin is also useful. Because they are found in grass, staying on trails, roads, or paths can prevent contact. Dusting sulfur is used commercially for mite control and can be used to control chiggers in yards. The dusting of shoes, socks and trouser legs with sulfur can be highly effective in repelling chiggers.

Another good strategy is to recognize the chigger habitat to avoid exposure in the first place. Chiggers in North America thrive late in summer, in dry tall grasses and other thick, unshaded vegetation. Insect repellents containing one of the following active ingredients are recommended: DEET, catnip oil extract (nepetalactone), citronella oil or eucalyptus oil extract. However, in 1993 issue a study reported on tests of two commercial repellents: DEET and citrus oil: "All chiggers exposed on the filter papers treated with DEET died and did not move off the treated papers. None of the chiggers that were placed on papers treated with citrus oil were killed." It was concluded that DEET was more effective than citrus oil.

Chiggers can also be treated using common household vinegar (5% acetic acid).

The majority of individuals who receive a sting from an insect experience local reactions. It is estimated that 5-10% of individuals will experience a generalized systemic reaction that can involve symptoms ranging from hives to wheezing and even anaphylaxis. In the United States approximately 40 people die each year from anaphylaxis due to stinging insect allergy. Potentially life-threatening reactions occur in 3% of adults and 0.4–0.8% of children.

An eschar (; Greek: "eschara") is a slough or piece of dead tissue that is cast off from the surface of the skin, particularly after a burn injury, but also seen in gangrene, ulcer, fungal infections, necrotizing spider bite wounds, spotted fevers and exposure to cutaneous anthrax. The term "eschar" is not interchangeable with "scab". An eschar contains necrotic tissue, whereas a scab is composed of dried blood and exudate.

Black eschars are most commonly attributed to anthrax, which may be contracted through herd animal exposure, but can also be obtained from "Pasteurella multocida" exposure in cats and rabbits. A newly identified human rickettsial infection, "R. parkeri" rickettsiosis, can be differentiated from Rocky Mountain spotted fever by the presence of an eschar at the site of inoculation.

Eschar is sometimes called a "black wound" because the wound is covered with thick, dry, black necrotic tissue.

Eschar may be allowed to slough off naturally, or it may require surgical removal (debridement) to prevent infection, especially in immunocompromised patients (e.g. if a skin graft is to be conducted).

If eschar is on a limb, it is important to assess peripheral pulses of the affected limb to make sure blood and lymphatic circulation is not compromised. If circulation is compromised, an escharotomy, or surgical incision through the eschar, may be indicated.

Immediate treatment consists of rinsing the bite site in cold water. If not too painful, ice the bite site. This constricts the blood vessels so the venom does not spread. Also recommended is papain, an enzyme that breaks down protein. Papain can be found in meat tenderizer and papaya. This deactivates the majority of the centipede venom's proteins. Depending on the type of centipede and level of envenomation, this treatment may not degrade the entire venom dose and residual pain will remain.

Individuals who are bitten by centipedes are sometimes given a urine test to check for muscle tissue breakdown and/or an EKG to check for heart and vascular problems.

Reassurance and pain relief is often given in the form of painkillers, such as non-steroidal anti-inflammatory medications, antihistamines and anti-anxiety medications. In a severe case the affected limb can be elevated and administered diuretic medications.

Wound care principles and sometimes antibiotics are used to keep the wound itself from becoming infected or necrotic.

In Barbados, a folk remedy involves applying a freshly cut onion to the site of the injury "bite" for 10 minutes. Repeat until relief is obtained.

Insect bites and stings occur when an insect is agitated and seeks to defend itself through its natural defense mechanisms, or when an insect seeks to feed off the bitten person. Some insects inject formic acid, which can cause an immediate skin reaction often resulting in redness and swelling in the injured area. Stings from fire ants, bees, wasps and hornets are usually painful, and may stimulate a dangerous allergic reaction called anaphylaxis for at-risk patients, and some wasps can also have a powerful bite along with a sting. Bites from mosquitoes and fleas are more likely to cause itching than pain.

The skin reaction to insect bites and stings usually lasts for up to a few days. However, in some cases the local reaction can last for up to two years. These bites are sometimes misdiagnosed as other types of benign or cancerous lesions.

The histomorphologic appearance of insect bites is usually characterized by a wedge-shaped superficial dermal perivascular infiltrate consisting of abundant lymphocytes and scattered eosinophils. This appearance is non-specific, i.e. it may be seen in a number of conditions including:

- Drug reactions,

- Urticarial reactions,

- Prevesicular early stage of bullous pemphigoid, and

- HIV related dermatoses.

To reduce the itching, an application of anti-itch cream containing hydrocortisone, calamine, or benzyl benzoate is often used (though calamine has been shown not to be effective). Hydrogen peroxide and capsaicin cream has also been effective. Another good way to relieve itching is to apply heat—either by using a hand held shower with water hot as one can stand, or by heating the bite with a hair dryer. The heat method will relieve itching for about four hours and will require repeating.

In some cases, the chigger is still present when the bite appears. A 10× magnifier can be used to see the chigger and it may be removed with fine-tipped tweezers. Once it is gone, covering the bite with nail polish, calamine lotion, vaseline or other petroleum jelly, baby oil, or anything else may help the pain and itching, but will neither suffocate the chigger nor help the bites heal any faster. Medication such as antihistamines or corticosteroid creams may be prescribed by doctors, and might help in some instances.

Insect sting allergy is the term commonly given to the allergic response of an animal in response to the bite or sting of an insect. Typically, insects which generate allergic responses are either stinging insects (wasps, bees, hornets and ants) or biting insects (mosquitoes, ticks). Stinging insects inject venom into their victims, whilst biting insects normally introduce anti-coagulants into their victims.

The great majority of insect allergic animals just have a simple allergic response – a reaction local to the sting site which appears as just a swelling arising from the release of histamine and other chemicals from the body tissues near to the sting site. The swelling, if allergic, can be helped by the provision of an anti-histamine ointment as well as an ice pack. This is the typical response for all biting insects and many people have this common reaction.

Mosquito allergy may result in a collection of symptoms called skeeter syndrome that occur after a bite. This syndrome may be mistaken for an infection such as cellulitis.

In anaphylactic patients the response is more aggressive leading to a systemic reaction where the response progresses from the sting site around the whole body. This is potentially something very serious and can lead to anaphylaxis, which is potentially life-threatening.

Ticks should be removed promptly and carefully with tweezers and by applying gentle, steady traction. The tick's body should not be crushed when it is removed and the tweezers should be placed as close to the skin as possible to avoid leaving tick mouthparts in the skin; mouthparts left in the skin can allow secondary infections. Ticks should not be removed with bare hands. Hands should be protected by gloves and/or tissues and thoroughly washed with soap and water after the removal process.

A match or flame should not be used to remove a tick. This method, once thought safe, can cause the tick to regurgitate, expelling any disease it may be carrying into the bite wound.

While obviously preventable by staying away from rodents, otherwise hands and face should be washed after contact and any scratches both cleaned and antiseptics applied. The effect of chemoprophylaxis following rodent bites or scratches on the disease is unknown. No vaccines are available for these diseases.

Improved conditions to minimize rodent contact with humans are the best preventive measures. Animal handlers, laboratory workers, and sanitation and sewer workers must take special precautions against exposure. Wild rodents, dead or alive, should not be touched and pets must not be allowed to ingest rodents.

Those living in the inner cities where overcrowding and poor sanitation cause rodent problems are at risk from the disease. Half of all cases reported are children under 12 living in these conditions.

When proper treatment is provided for patients with rat-bite fever, the prognosis is positive. Without treatment, the infection usually resolves on its own, although it may take up to a year to do so. A particular strain of rat-bite fever in the United States can progress and cause serious complications that can be potentially fatal. Before antibiotics were used, many cases resulted in death. If left untreated, streptobacillary rat-bite fever can result in infection in the lining of the heart, covering over the spinal cord and brain, or in the lungs. Any tissue or organ throughout the body may develop an abscess.