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.

The introduction of cinchona into therapeutics was due to the discovery of its efficacy in malaria. In 1921, John used quinine hydrochloride, an alkaloid of cinchona in the treatment of amoebic liver abscess.

Later when synthetic derivatives of quinine were introduced, chloroquine phosphate, a 4-aminoquinoline was found to be less toxic than the parent drug. The drug was first quoted in the treatment of this condition in very early reports by Conan (1948)15, Murgatroyd and Kent (1948).

It is absorbed rapidly and completely from the gastrointestinal tract. It is found to be very effective in invasive amoebiasis although the drug is a weaker amoebicide when compared to emetine. It is only feebly amoebicidal in the intestinal lumen.

The high concentration in the liver parenchyma and the lung allows the drug to act upon E. Histolytica in cases of amoebic liver abscess and pleuropulmonary amoebiasis.

It is usually well tolerated, but in some individuals it may cause mild headache, itching, nausea, vomiting or blurred vision. Rarely incoordination, convulsions, peripheral neuritis and bleaching of hair can occur. Diminution of T waves has been noticed on routine electrocardiographic recordings. Retinopathy does not occur with the usual dosage for amoebic liver abscess. Psychic disturbances though rare may interfere with the safe operation of machines and vehicles. The drug may be toxic to children in large doses18 and causes deafness in the foetus.

Each 0.5 G. tablet contains chloroquine diphosphate equivalent to 0.3 G. of the base. For the treatment of amoebic liver abscess, it is administered in doses of 0.6 G. base per day in 2 to 3 divided doses orally for 2 days followed by 0.15 G. base twice daily for 2 to 3 weeks. However, Plorde recommends that it be given as 0.6 G. base initially, 0.3 G. base six hours later and then 0.3 G. base twice daily for fourteen to twenty eight days.19 Chloroquine is also available in an injectable form. Since it is quite toxic by this route, it should not be used for more than 24–48 hours after which oral therapy should be continued. Rarely, when patients of amoebic liver abscess are vomiting, injection chloroquine can be used in a dose of 0.3–0.6 G. base in 24 hours not exceeding 0.9 G.).

Chloroquine given alone is a safer drug than emetine in amoebic liver abscess, but unfortunately the relapse rate is almost 25%. Rarely repetition of the course may induce a dramatic response.

On the basis of the laboratory evidence and case reports, amphotericin B has been the traditional mainstay of PAM treatment since the first reported survivor in the United States in 1982.

Treatment has often also used combination therapy with multiple other antimicrobials in addition to amphotericin, such as fluconazole, miconazole, rifampicin and azithromycin. They have shown limited success only when administered early in the course of an infection. Fluconazole is commonly used as it has been shown to have synergistic effects against naegleria when used with amphotericin in-vitro.

While the use of rifampicin has been common, including in all four North American cases of survival, its continued use has been questioned. It only has variable activity in-vitro and it has strong effects on the therapeutic levels of other antimicrobials used by inducing cytochrome p450 pathways.

In 2013, the two most recent successfully treated cases in the United States utilized drug combinations that included the medication miltefosine as well as targeted temperature management to manage brain swelling that is secondary to the infection. As of 2015 there were no data on how well miltefosine is able to reach the central nervous system. As of 2015 the U.S. CDC offered miltefosine to doctors for the treatment of free-living ameobas including naegleria.

"E. histolytica" infections occur in both the intestine and (in people with symptoms) in tissue of the intestine and/or liver. As a result, two different classes of drugs are needed to treat the infection, one for each location. Such anti-amoebic drugs are known as amoebicides.

Dysentery is managed by maintaining fluids by using oral rehydration therapy. If this treatment cannot be adequately maintained due to vomiting or the profuseness of diarrhea, hospital admission may be required for intravenous fluid replacement. In ideal situations, no antimicrobial therapy should be administered until microbiological microscopy and culture studies have established the specific infection involved. When laboratory services are not available, it may be necessary to administer a combination of drugs, including an amoebicidal drug to kill the parasite, and an antibiotic to treat any associated bacterial infection.

If shigellosis is suspected and it is not too severe, letting it run its course may be reasonable — usually less than a week. If the case is severe, antibiotics such as ciprofloxacin or TMP-SMX may be useful. However, many strains of "Shigella" are becoming resistant to common antibiotics, and effective medications are often in short supply in developing countries. If necessary, a doctor may have to reserve antibiotics for those at highest risk for death, including young children, people over 50, and anyone suffering from dehydration or malnutrition.

Amoebic dysentery is often treated with two antimicrobial drug such as metronidazole and paromomycin or iodoquinol.

Lemierre's syndrome is primarily treated with antibiotics given intravenously. "Fusobacterium necrophorum" is generally highly susceptible to beta-lactam antibiotics, metronidazole, clindamycin and third generation cephalosporins while the other fusobacteria have varying degrees of resistance to beta-lactams and clindamycin. Additionally, there may exist a co-infection by another bacterium. For these reasons is often advised not to use monotherapy in treating Lemierre's syndrome. Penicillin and penicillin-derived antibiotics can thus be combined with a beta-lactamase inhibitor such as clavulanic acid or with metronidazole. Clindamycin can be given as monotherapy.

If antibiotic therapy does not improve the clinical picture, it may prove useful to drain any abscesses and/or perform ligation of the internal jugular vein where the antibiotic can not penetrate.

There is no evidence to opt for or against the use of anticoagulation therapy. The low incidence of Lemierre's syndrome has not made it possible to set up clinical trials to study the disease.

The disease can often be untreatable, especially if other negative factors occur, i.e. various diseases occurring at the same time, such as meningitis, pneumonia.

Michael Beach, a recreational waterborne illness specialist for the Centers for Disease Control and Prevention, stated in remarks to the Associated Press that wearing of nose-clips to prevent insufflation of contaminated water would be effective protection against contracting PAM, noting that "You'd have to have water going way up in your nose to begin with".

Advice stated in the press release from Taiwan's Centers for Disease Control recommended people prevent fresh water from entering the nostrils and avoid putting their heads down into fresh water or stirring mud in the water with feet. When starting to suffer from fever, headache, nausea, or vomiting subsequent to any kind of exposure to fresh water even if the belief in none of the fresh water has traveled through nostrils, people with such conditions should be carried to hospital quickly and make sure doctors are well-informed about the history of exposure to fresh water.

With correct treatment, most cases of amoebic and bacterial dysentery subside within 10 days, and most individuals achieve a full recovery within two to four weeks after beginning proper treatment. If the disease is left untreated, the prognosis varies with the immune status of the individual patient and the severity of disease. Extreme dehydration can delay recovery and significantly raises the risk for serious complications.

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.

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 one case, cloxacillin, ceftriaxone, and amphotericin B were tried.

Two patients survived after being successfully treated with a therapy consisting of flucytosine, pentamidine, fluconazole, sulfadiazine and azithromycin. Thioridazine was also given. Successful treatment in these cases was credited to "awareness of "Balamuthia" as the causative agent of encephalitis and early initiation of antimicrobial therapy."

In the majority of cases, amoebas remain in the gastrointestinal tract of the hosts. Severe ulceration of the gastrointestinal mucosal surfaces occurs in less than 16% of cases. In fewer cases, the parasite invades the soft tissues, most commonly the liver. Only rarely are masses formed (amoebomas) that lead to intestinal obstruction.(Mistaken for Ca caecum and appendicular mass) Other local complications include bloody diarrhea, pericolic and pericaecal abscess.

Complications of hepatic amoebiasis includes subdiaphragmatic abscess, perforation of diaphragm to pericardium and pleural cavity, perforation to abdominal cavital "(amoebic peritonitis)" and perforation of skin "(amoebiasis cutis)".

Pulmonary amoebiasis can occur from hepatic lesion by haemotagenous spread and also by perforation of pleural cavity and lung. It can cause lung abscess, pulmono pleural fistula, empyema lung and broncho pleural fistula. It can also reach the brain through blood vessels and cause amoebic brain abscess and amoebic meningoencephalitis. Cutaneous amoebiasis can also occur in skin around sites of colostomy wound, perianal region, region overlying visceral lesion and at the site of drainage of liver abscess.

Urogenital tract amoebiasis derived from intestinal lesion can cause amoebic vulvovaginitis "(May's disease)", rectovesicle fistula and rectovaginal fistula.

"Entamoeba histolytica" infection is associated with malnutrition and stunting of growth.

Even with treatment, the condition is often fatal, and there are very few recorded survivors, almost all of whom suffered permanent neurocognitive deficits. Antifungal drugs including ketoconazole, miconazole, 5-flucytosine and pentamidine have been shown to be effective against GAE-causing organisms in laboratory tests.

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.

Eye and skin infections caused by "Acanthamoeba spp." are generally treatable. Topical use of 0.1% propamidine isethionate (Brolene) plus neomycin-polymyxin B-gramicidin ophthalmic solution has been a successful approach; keratoplasty is often necessary in severe infections. Although most cases of brain (CNS) infection with "Acanthamoeba" have resulted in death, patients have recovered from the infection with proper treatment.

Treatment depends on many factors, such as the age of horse, severity of symptoms and duration of infection. As long a horse is eating and drinking, the infection must run its course, much like a common cold virus. Over time a horse will build up enough antibodies to overtake and fight the disease. Other treatment options can be applying heat packs to abscesses to help draw it to the surface and using drawing salves such as Ichthammol. A blood test or bacterial cultures can be taken to confirm the horse is fighting Pigeon Fever. Anti-inflammatory such as phenylbutazone can be used to ease pain and help control swelling. Treating Pigeon Fever with antibiotics is not normally recommended for external abscesses since it is a strong bacterium that takes extended treatment to kill off and to ensure it does not return stronger. However, if the abscesses are internal then antibiotics may be needed. Consulting a veterinarian for treatment is recommended. Making the horse comfortable, ensuring the horse has good food supply and quality hay will help the horse keep their immune system strong to fight off the infection. Once the abscess breaks or pops, it will drain for a week or two. During this time keeping the area clean, applying hot packs or drawing salves will help remove the pus that has gathered in the abscess.

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.

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.

Currently, the most effective treatment is transferring the affected fish to a freshwater bath for a period of 2 to 3 hours. This is achieved by towing the sea cages into fresh water, or pumping the fish from the sea cage to a tarp filled with fresh water. Mortality rates have been lowered by adding Levamisole to the water until the saturation is above 10ppm. Due to the difficulty and expense of treatment, the productivity of salmon aquaculture is limited by access to a source of fresh water. Chloramine and chlorine dioxide have also been used. Other potential in-feed treatments such as immunosupportive-based feeds, mucolytic compounds such as L-cysteine ethyl ester and the parasticide bithionol have been tested with some success although not developed for commercial use.

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%.

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.

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

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.

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.

Most cases respond to antibiotics and prognosis is usually excellent unless there is a debilitating underlying condition. Mortality from lung abscess alone is around 5% and is improving.