Most people who have an uncomplicated skin abscess should not use antibiotics. Antibiotics in addition to standard incision and drainage is recommended in persons with severe abscesses, many sites of infection, rapid disease progression, the presence of cellulitis, symptoms indicating bacterial illness throughout the body, or a health condition causing immunosuppression. People who are very young or very old may also need antibiotics. If the abscess does not heal only with incision and drainage, or if the abscess is in a place that is difficult to drain such as the face, hands, or genitals, then antibiotics may be indicated.

In those cases of abscess which do require antibiotic treatment, "Staphylococcus aureus" bacteria is a common cause and an anti-staphylococcus antibiotic such as flucloxacillin or dicloxacillin is used. The Infectious Diseases Society of America advises that the draining of an abscess is not enough to address community-acquired methicillin-resistant "Staphylococcus aureus" (MRSA), and in those cases, traditional antibiotics may be ineffective. Alternative antibiotics effective against community-acquired MRSA often include clindamycin, doxycycline, minocycline, and trimethoprim-sulfamethoxazole. The American College of Emergency Physicians advises that typical cases of abscess from MRSA get no benefit from having antibiotic treatment in addition to the standard treatment. If the condition is thought to be cellulitis rather than abscess, consideration should be given to possibility of strep species as cause that are still sensitive to traditional anti-staphylococcus agents such as dicloxacillin or cephalexin in patients able to tolerate penicillin. Antibiotic therapy alone without surgical drainage of the abscess is seldom effective due to antibiotics often being unable to get into the abscess and their ineffectiveness at low pH levels.

Culturing the wound is not needed if standard follow-up care can be provided after the incision and drainage. Performing a wound culture is unnecessary because it rarely gives information which can be used to guide treatment.

Antibiotics are commonly used as a curing method for pancreatic abscesses although their role remains controversial. Prophylactic antibiotics are normally chosen based on the type of flora and the degree of antibiotic penetration into the abscess. Pancreatic abscesses are more likely to host enteric organisms and pathogens such as "E. coli", "Klebsiella pneumonia", "Enterococcus faecalis", "Staphylococcus aureus", "Pseudomonas aeruginosa", "Proteus mirabilis", and "Streptococcus" species. Medical therapy is usually given to people whose general health status does not allow surgery. On the other hand, antibiotics are not recommended in patients with pancreatitis, unless the presence of an infected abscess has been proved.

Although there have been reported cases of patients who were given medical treatment and survived, primary drainage of the abscess is the main treatment used to cure this condition. Drainage usually involves a surgical procedure. It has been shown that CT-guided drainage brought inferior results than open drainage. Hence, open surgical procedure is preferred to successfully remove the abscess. However, CT-guided drainage is the option treatment for patients who may not tolerate an open procedure. Endoscopic treatment is at the same time a treatment option that increased in popularity over the last years.

In North America, after drainage, an abscess cavity is often packed, perhaps with cloth, in an attempt to protect the healing wound. However, evidence from emergency medicine literature reports that packing wounds after draining causes pain to the person and does not decrease the rate of recurrence, bring more rapid healing, or lead to fewer physician visits.

Treatment is by removing the pus, antibiotics, sufficient fluids, and pain medication. Steroids may also be useful. Admission to hospital is generally not needed.

The treatment includes lowering the increased intracranial pressure and starting intravenous antibiotics (and meanwhile identifying the causative organism mainly by blood culture studies).

Hyperbaric oxygen therapy (HBO2 or HBOT) is indicated as a primary and adjunct treatment which provides four primary functions.

Firstly, HBOT reduces intracranial pressure. Secondly, high partial pressures of oxygen act as a bactericide and thus inhibits the anaerobic and functionally anaerobic flora common in brain abscess. Third, HBOT optimizes the immune function thus enhancing the host defense mechanisms and fourth, HBOT has been found to be of benefit when brain abscess is concomitant with cranial osteomyleitis.

Secondary functions of HBOT include increased stem cell production and up-regulation of VEGF which aid in the healing and recovery process.

Surgical drainage of the abscess remains part of the standard management of bacterial brain abscesses. The location and treatment of the primary lesion also crucial, as is the removal of any foreign material (bone, dirt, bullets, and so forth).

There are few exceptions to this rule: "Haemophilus influenzae" meningitis is often associated with subdural effusions that are mistaken for subdural empyemas. These effusions resolve with antibiotics and require no surgical treatment. Tuberculosis can produce brain abscesses that look identical to conventional bacterial abscesses on CT imaging. Surgical drainage or aspiration is often necessary to identify "Mycobacterium tuberculosis", but once the diagnosis is made no further surgical intervention is necessary.

CT guided stereotactic aspiration is also indicated in the treatment of brain abscess.

The infection is frequently penicillin resistant. There are a number of antibiotics options including amoxicillin/clavulanate, clindamycin, or metronidazole in combination with benzylpenicillin (penicillin G) or penicillin V. Piperacillin/tazobactam may also be used.

RPA's frequently require surgical intervention. A tonsillectomy approach is typically used to access/drain the abscess, and the outcome is usually positive. Surgery in adults may be done without general anesthesia because there is a risk of abscess rupture during tracheal intubation. This could result in pus from the abscess aspirated into the lungs. In complex cases, an emergency tracheotomy may be required to prevent upper airway obstruction caused by edema in the neck.

High-dose intravenous antibiotics are required in order to control the infection and reduce the size of the abscess prior to surgery.

Chronic retropharyngeal abscess is usually secondary to tuberculosis and the patient needs to be started on anti-tubercular therapy as soon as possible.

The outlook is generally based on the severity of the infection. It is however a severe complication which may result in the death of the patient if the appropriate treatment is not administered. Patients are at risk of sepsis and multiple organ failure and in cases in which the infected abscess is not removed through surgery, the mortality rate can reach 100%.

Treatment has traditionally been splenectomy. However, splenectomy is avoided if possible, particularly in children, to avoid the resulting permanent susceptibility to bacterial infections. Most small, and some moderate-sized lacerations in stable patients (particularly children) are managed with hospital observation and sometimes transfusion rather than surgery. Embolization, blocking off of the hemorrhaging vessels, is a newer and less invasive treatment. When surgery is needed, the spleen can be surgically repaired in a few cases, but splenectomy is still the primary surgical treatment, and has the highest success rate of all treatments.

Incision drainage with proper evacuation of the fluid followed by anti-tubercular medication.

Splenic infarction can be induced for the treatment of such conditions as portal hypertension or splenic injury. It can also be used prior to splenectomy for the prevention of blood loss.

Antibiotics are usually prescribed, with the agent selected based on suspected organism and presence or absence of purulence, although the best treatment choice is unclear. If an abscess is also present, surgical drainage is usually indicated, with antibiotics often prescribed for co-existent cellulitis, especially if extensive. Pain relief is also often prescribed, but excessive pain should always be investigated, as it is a symptom of necrotizing fasciitis. Elevation of the affected area is often recommended.

Steroids may speed recovery in those on antibiotics.

The treatment of invasive amoebiasis should be directed to all sites where "E. histolytica" may be present. Hence the ideal amoebicide should be able to act within the intestinal lumen, in the intestinal wall, and systemically, particularly in the liver.

Systemic amoebicidal drugs include emetine, dehydroemetine, chloroquine diphosphate, metronidazole, and tinidazole.

Anal abscesses are rarely treated with a simple course of antibiotics. In almost all cases surgery will need to take place to remove the abscess. Treatment is possible in an emergency room under local anesthesia, but it is highly preferred to be formally admitted to a hospital and to have the surgery performed in an operating room under general anesthesia.

Generally speaking, a fairly small but deep incision is performed close to the root of the abscess. The surgeon will allow the abscess to drain its exudate and attempt to discover any other related lesions in the area. This is one of the most basic types of surgery, and is usually performed in less than thirty minutes by the anal surgical team. Generally, a portion of the exudate is sent for microbiological analysis to determine the type of infecting bacteria. The incision is not closed (stitched), as the damaged tissues must heal from the inside toward the skin over a period of time.

The affected individual is often sent home within twenty-four hours of the surgery, and may be instructed to perform several 'sitz baths' per day, whereby a small basin (which usually fits over a toilet) is filled with warm water (and possibly, salts) and the affected area is soaked for a period of time. Another method of recovery involves the use of surgical packing, which is initially inserted by the surgical team, with redressing generally performed by hospital staff or a District Nurse (however, following the results of several double-blind studies, the effectiveness of surgical packing has come into question). During the week following the surgery, many patients will have some form of antibiotic therapy, along with some form of pain management therapy, consistent with the nature of the abscess.

The patient usually experiences an almost complete relief of the severe pain associated to his/her abscess upon waking from anesthesia; the pain associated with the opening and draining incision during the post-operative period is often mild in comparison.

Mainly surgical approach has to be taken.

If cavity is small then surgical evacuation & curettage is performed under antibiotic cover.

If cavity is large then after evacuation, packing with cancellous bone chips

It is a synthetic compound developed by Osbond "et al." and Brossi "et al." in 1959. It is as effective as emetine in its amoebicidal properties. Given parenterally dehydroemetine is surprisingly painless. Oral tablets have been introduced. But for some reason, these tablets have not become popular. A high cure rate can be obtained with this drug. Compared to emetine, its concentration in the heart is less. Electrocardiographic changes are not seen so often. When present, they are more transient than with emetine.

Dehydroemetine is excreted by the kidneys, heart and the other organs more rapidly than emetine. Therefore, a daily dose of 1.25 mg or 1.5 mg/kg body weight is necessary. The total daily dose should not exceed 90 mg. The course should not be repeated in less than 14 days.

If the splenomegaly underlies hypersplenism, a splenectomy is indicated and will correct the hypersplenism. However, the underlying cause of the hypersplenism will most likely remain; consequently, a thorough diagnostic workup is still indicated, as, leukemia, lymphoma and other serious disorders can cause hypersplenism and splenomegaly. After splenectomy, however, patients have an increased risk for infectious diseases.

Patients undergoing splenectomy should be vaccinated against "Haemophilus influenzae", "Streptococcus pneumoniae", and "Meningococcus". They should also receive annual influenza vaccinations. Long-term prophylactic antibiotics may be given in certain cases.

In cases of infectious mononucleosis splenomegaly is a common symptom and health care providers may consider using abdominal ultrasonography to get insight into a person's condition. However, because spleen size varies greatly, ultrasonography is not a valid technique for assessing spleen enlargement and should not be used in typical circumstances or to make routine decisions about fitness for playing sports.

Because a splenic rupture permits large amounts of blood to leak into the abdominal cavity, it can result in shock and death. Generally a nonoperative approach is chosen in those who are hemodynamically stable with non-worsening symptoms. During this period of nonoperative management strict bed rest between 24–72 hours with careful monitoring along with a CT 7 days after the injury.

If an individual's spleen is enlarged, as is frequent in mononucleosis, most physicians will advise against activities (such as contact sports) where injury to the abdomen could be catastrophic.

Patients whose spleens have been removed must receive immunizations to help prevent infections such as pneumonia. This helps to replace the lost function of this organ.

Broadspectrum antibiotic to cover mixed flora is the mainstay of treatment. Pulmonary physiotherapy and postural drainage are also important. Surgical procedures are required in selective patients for drainage or pulmonary resection.

Antibiotics choices depend on regional availability, but a penicillinase-resistant semisynthetic penicillin or a first-generation cephalosporin is currently recommended for cellulitis without abscess. A course of antibiotics is not effective in between 6 and 37% of cases.

Treatment generally consists of surgical drainage, and long-term (6 to 8 weeks) use of antibiotics.

Treatment of hemosuccus pancreaticus depends on the source of the hemorrhage. If the bleeding is identified on angiography to be coming from a vessel that is small enough to occlude, embolization through angiography may stop the bleeding. Both coils in the end-artery and stents across the area of bleeding have been used to control the hemorrhage. However, the bleeding may be refractory to the embolization, which would necessitate surgery to remove the pancreas at the source of hemorrhage. Also, the cause of bleeding may be too diffuse to be treated with embolization (such as with pancreatitis or with pancreatic cancer). This may also require surgical therapy, and usually a distal pancreatectomy, or removal of the part of the pancreas from the area of bleeding to the tail, is required.

Abdominal pain is often the predominant symptom in patients with acute pancreatitis and should be treated with analgesics.

Opioids are safe and effective at providing pain control in patients with acute pancreatitis. Adequate pain control requires the use of intravenous opiates, usually in the form of a patient-controlled analgesia pump. Hydromorphone or fentanyl (intravenous) may be used for pain relief in acute pancreatitis. Fentanyl is being increasingly used due to its better safety profile, especially in renal impairment. As with other opiates, fentanyl can depress respiratory function. It can be given both as a bolus as well as constant infusion.

Meperidine has been historically favored over morphine because of the belief that morphine caused an increase in sphincter of Oddi pressure. However, no clinical studies suggest that morphine can aggravate or cause pancreatitis or cholecystitis. In addition, meperidine has a short half-life and repeated doses can lead to accumulation of the metabolite normeperidine, which causes neuromuscular side effects and, rarely, seizures.

Recovery from an anaerobic infection depends on adequate and rapid management. The main principles of managing anaerobic infections are neutralizing the toxins produced by anaerobic bacteria, preventing the local proliferation of these organisms by altering the environment and preventing their dissemination and spread to healthy tissues.

Toxin can be neutralized by specific antitoxins, mainly in infections caused by Clostridia (tetanus and botulism). Controlling the environment can be attained by draining the pus, surgical debriding of necrotic tissue, improving blood circulation, alleviating any obstruction and by improving tissue oxygenation. Therapy with hyperbaric oxygen (HBO) may also be useful. The main goal of antimicrobials is in restricting the local and systemic spread of the microorganisms.

The available parenteral antimicrobials for most infections are metronidazole, clindamycin, chloramphenicol, cefoxitin, a penicillin (i.e. ticarcillin, ampicillin, piperacillin) and a beta-lactamase inhibitor (i.e. clavulanic acid, sulbactam, tazobactam), and a carbapenem (imipenem, meropenem, doripenem, ertapenem). An antimicrobial effective against Gram-negative enteric bacilli (i.e. aminoglycoside) or an anti-pseudomonal cephalosporin (i.e. cefepime ) are generally added to metronidazole, and occasionally cefoxitin when treating intra-abdominal infections to provide coverage for these organisms. Clindamycin should not be used as a single agent as empiric therapy for abdominal infections. Penicillin can be added to metronidazole in treating of intracranial, pulmonary and dental infections to provide coverage against microaerophilic streptococci, and Actinomyces.

Oral agents adequate for polymicrobial oral infections include the combinations of amoxicillin plus clavulanate, clindamycin and metronidazole plus a macrolide. Penicillin can be added to metronidazole in the treating dental and intracranial infections to cover "Actinomyces" spp., microaerophilic streptococci, and "Arachnia" spp. A macrolide can be added to metronidazole in treating upper respiratory infections to cover "S. aureus" and aerobic streptococci. Penicillin can be added to clindamycin to supplement its coverage against "Peptostreptococcus" spp. and other Gram-positive anaerobic organisms.

Doxycycline is added to most regimens in the treatment of pelvic infections to cover chlamydia and mycoplasma. Penicillin is effective for bacteremia caused by non-beta lactamase producing bacteria. However, other agents should be used for the therapy of bacteremia caused by beta-lactamase producing bacteria.

Because the length of therapy for anaerobic infections is generally longer than for infections due to aerobic and facultative anaerobic bacteria, oral therapy is often substituted for parenteral treatment. The agents available for oral therapy are limited and include amoxacillin plus clavulanate, clindamycin, chloramphenicol and metronidazole.

In 2010 the American Surgical Society and American Society of Infectious Diseases have updated their guidelines for the treatment of abdominal infections.

The recommendations suggest the following:

For mild-to-moderate community-acquired infections in adults, the agents recommended for empiric regimens are: ticarcillin- clavulanate, cefoxitin, ertapenem, moxifloxacin, or tigecycline as single-agent therapy or combinations of metronidazole with cefazolin, cefuroxime, ceftriaxone, cefotaxime, levofloxacin, or ciprofloxacin. Agents no longer recommended are: cefotetan and clindamycin ( Bacteroides fragilis group resistance) and ampicillin-sulbactam (E. coli resistance) and ainoglycosides (toxicity).

For high risk community-acquired infections in adults, the agents recommended for empiric regimens are: meropenem, imipenem-cilastatin, doripenem, piperacillin-tazobactam, ciprofloxacin or levofloxacin in combination with metronidazole, or ceftazidime or cefepime in combination with metronidazole. Quinolones should not be used unless hospital surveys indicate >90% susceptibility of "E. coli" to quinolones.

Aztreonam plus metronidazole is an alternative, but addition of an agent effective against gram-positive cocci is recommended. The routine use of an aminoglycoside or another second agent effective against gram-negative facultative and aerobic bacilli is not recommended in the absence of evidence that the infection is caused by resistant organisms that require such therapy.

Empiric use of agents effective against enterococci is recommended and agents effective against methicillin-resistant "S. aureus" (MRSA) or yeast is not recommended in the absence of evidence of infection due to such organisms.

Empiric antibiotic therapy for health care-associated intra-abdominal should be driven by local microbiologic results. Empiric coverage of likely pathogens may require multidrug regimens that include agents with expanded spectra of activity against gram-negative aerobic and facultative bacilli. These include meropenem, imipenem-cilastatin, doripenem, piperacillin-tazobactam, or ceftazidime or cefepime in combination with metronidazole. Aminoglycosides or colistin may be required.

Antimicrobial regimens for children include an aminoglycoside-based regimen, a carbapenem (imipenem, meropenem, or ertapenem), a beta-lactam/beta-lactamase-inhibitor combination (piperacillin-tazobactam or ticarcillin-clavulanate), or an advanced-generation cephalosporin (cefotaxime, ceftriaxone, ceftazidime, or cefepime) with metronidazole.

Clinical judgment, personal experience, safety and patient compliance should direct the physician in the choice of the appropriate antimicrobial agents. The length of therapy generally ranges between 2 and 4 weeks, but should be individualized depending on the response. In some instances treatment may be required for as long as 6–8 weeks, but can often be shortened with proper surgical drainage.

If ear infections are treated in a reasonable amount of time, the antibiotics will usually cure the infection and prevent its spread. For this reason, mastoiditis is rare in developed countries. Most ear infections occur in infants as the eustachian tubes are not fully developed and don't drain readily.

In all developed countries with up-to-date modern healthcare the primary treatment for mastoiditis is administration of intravenous antibiotics. Initially, broad-spectrum antibiotics are given, such as ceftriaxone. As culture results become available, treatment can be switched to more specific antibiotics directed at the eradication of the recovered aerobic and anaerobic bacteria. Long-term antibiotics may be necessary to completely eradicate the infection. If the condition does not quickly improve with antibiotics, surgical procedures may be performed (while continuing the medication). The most common procedure is a myringotomy, a small incision in the tympanic membrane (eardrum), or the insertion of a tympanostomy tube into the eardrum. These serve to drain the pus from the middle ear, helping to treat the infection. The tube is extruded spontaneously after a few weeks to months, and the incision heals naturally. If there are complications, or the mastoiditis does not respond to the above treatments, it may be necessary to perform a mastoidectomy: a procedure in which a portion of the bone is removed and the infection drained.