Treatment for both pregnant and non-pregnant women is usually with metronidazole, by mouth once. Caution should be used in pregnancy, especially in the first trimester. Sexual partners, even if they have no symptoms, should also be treated.

For 95-97% of cases, infection is resolved after one dose of metronidazole. Studies suggest that 4-5% of trichomonas cases are resistant to metronidazole, which may account for some “repeat” cases. Without treatment, trichomoniasis can persist for months to years in women, and is thought to improve without treatment in men. Women living with HIV infection have better cure rates if treated for 7 days rather than with one dose.

Topical treatments are less effective than oral antibiotics due to Skene's gland and other genitourinary structures acting as a reservoir.

"C. trachomatis" infection can be effectively cured with antibiotics. Guidelines recommend azithromycin, doxycycline, erythromycin, levofloxacin or ofloxacin. Agents recommended during pregnancy include erythromycin or amoxicillin.

An option for treating sexual partners of those with chlamydia or gonorrhea include patient-delivered partner therapy (PDT or PDPT), which is the practice of treating the sex partners of index cases by providing prescriptions or medications to the patient to take to his/her partner without the health care provider first examining the partner.

Following treatment people should be tested again after three months to check for reinfection.

Evidence from a randomized controlled trials for screening pregnant women who do not have symptoms for infection with trichomoniasis and treating women who test positive for the infection have not consistently shown a reduced risk of preterm birth. Further studies are needed to verify this result and determine the best method of screening. In the US, screening of pregnant women without any symptoms is only recommended in those with HIV as trichomonas infection is associated with increased risk of transmitting HIV to the fetus.

It is recommended that sexual partners be tested and potentially treated. One option for treating sexual partners of people infected is patient-delivered partner therapy (PDPT), which involves providing prescriptions or medications to the person to take to his/her partner without the health care provider's first examining him/her.

The United States' Centers for Disease Control and Prevention (CDC) currently recommend that individuals who have been diagnosed and treated for gonorrhea avoid sexual contact with others until at least one week past the final day of treatment in order to prevent the spread of the bacterium.

As of 2010, injectable ceftriaxone is one of the few effective antibiotics. This is typically given in combination with either azithromycin or doxycycline. As of 2015 and 2016 the CDC and WHO only recommends both ceftriaxone and azithromycin. Because of increasing rates of antibiotic resistance local susceptibility patterns must be taken into account when deciding on treatment.

Treatment involves antibiotics and may involve drainage of the buboes or abscesses by needle aspiration or incision. Further supportive measure may need to be taken: dilatation of the rectal stricture, repair of rectovaginal fistulae, or colostomy for rectal obstruction.

Common antibiotic treatments include: tetracycline (doxycycline) (all tetracyclines, including doxycycline, are contraindicated during pregnancy and in children due to effects on bone development and tooth discoloration), and erythromycin. Azithromycin is also a drug of choice in LGV.

As with all STIs, sex partners of patients who have LGV should be examined and tested for urethral or cervical chlamydial infection. After a positive culture for chlamydia, clinical suspicion should be confirmed with testing to distinguish serotype. Antibiotic treatment should be started if they had sexual contact with the patient during the 30 days preceding onset of symptoms in the patient. Patients with a sexually transmitted disease should be tested for other STDs due to high rates of comorbid infections. Antibiotics are not without risks and prophylaxtic broad antibiotic coverage is not recommended.

If symptomatic, testing is recommended. The risk of contracting Micoplasma infection can be reduced by the following:

- Using barrier methods such as condoms

- Seeking medical attention if you are experiencing symptoms suggesting a sexually transmitted infection.

- Seeking medical attention after learning that a current or former sex partner has, or might have had a sexually transmitted infection.

- Getting a STI history from your current partner and insisting they be tested and treated before intercourse.

- Avoiding vaginal activity, particularly intercourse, after the end of a pregnancy (delivery, miscarriage, or abortion) or certain gynecological procedures, to ensure that the cervix closes.

- Abstinence

Mycoplasmas have a triple-layered membrane and lack a cell wall. Commonly used antibiotics are generally ineffective because their efficacy is due to their ability to inhibit cell wall synthesis. Micoplasmas are not affected by penicillins and other antibiotics that act on the cell wall. The growth of micoplasmas in their host is inhibited by other broad-spectrum antibiotics. These broad-spectrum antibiotics inhibit the multiplication of the mycoplasma but does not kill them. Tetracyclines, macrolides, erythromycin, macrolides, ketolides, quinolones are used to treat mycoplasma infections. In addition to the penicillins, mycoplasmas are resistant to rifampicin. Mycoplasmas may be difficult to eradicate from human or animal hosts or from cell cultures by antibiotic treatment because of resistance to the antibiotic, or because it does not kill the mycoplasma cell. Mycoplasma cells are able to invade the cells of their hosts.

Treatment is often started without confirmation of infection because of the serious complications that may result from delayed treatment. Treatment depends on the infectious agent and generally involves the use of antibiotic therapy. If there is no improvement within two to three days, the patient is typically advised to seek further medical attention. Hospitalization sometimes becomes necessary if there are other complications. Treating sexual partners for possible STIs can help in treatment and prevention.

For women with PID of mild to moderate severity, parenteral and oral therapies appear to be effective. It does not matter to their short- or long-term outcome whether antibiotics are administered to them as inpatients or outpatients. Typical regimens include cefoxitin or cefotetan plus doxycycline, and clindamycin plus gentamicin. An alternative parenteral regimen is ampicillin/sulbactam plus doxycycline. Erythromycin-based medications can also be used. Another alternative is to use a parenteral regimen with ceftriaxone or cefoxitin plus doxycycline. Clinical experience guides decisions regarding transition from parenteral to oral therapy, which usually can be initiated within 24–48 hours of clinical improvement.

No treatment required. It is standard practice for men with infertility and category IV prostatitis to be given a trial of antibiotics and/or anti-inflammatories, although evidence of efficacy are weak. Since signs of asymptomatic prostatic inflammation may sometimes be associated with prostate cancer, this can be addressed by tests that assess the ratio of free-to-total PSA. The results of these tests were significantly different in prostate cancer and category IV prostatitis in one study.

The mainstay of treatment is antibiotics. Phenazopyridine is occasionally prescribed during the first few days in addition to antibiotics to help with the burning and urgency sometimes felt during a bladder infection. However, it is not routinely recommended due to safety concerns with its use, specifically an elevated risk of methemoglobinemia (higher than normal level of methemoglobin in the blood). Acetaminophen (paracetamol) may be used for fevers. There is no good evidence for the use of cranberry products for treating current infections.

Uncomplicated infections can be diagnosed and treated based on symptoms alone. Antibiotics taken by mouth such as trimethoprim/sulfamethoxazole (TMP/SMX), nitrofurantoin, or fosfomycin are typically first line. Cephalosporins, amoxicillin/clavulanic acid, or a fluoroquinolone may also be used. However, resistance to fluoroquinolones among the bacterial that cause urinary infections has been increasing. The FDA recommends against the use of fluoroquinolones when other options are available due to higher risks of serious side effects. These medications substantially shorten the time to recovery with all being equally effective. A three-day treatment with trimethoprim, TMP/SMX, or a fluoroquinolone is usually sufficient, whereas nitrofurantoin requires 5–7 days. Fosfomycin may be used as a single dose but has been associated with lower rates of efficacy.

With treatment, symptoms should improve within 36 hours. About 50% of people will recover without treatment within a few days or weeks. Fluoroquinolones are not recommended as a first treatment. The Infectious Diseases Society of America states this due to the concern of generating resistance to this class of medication. Amoxicillin-clavulanate appears less effective than other options. Despite this precaution, some resistance has developed to all of these medications related to their widespread use. Trimethoprim alone is deemed to be equivalent to TMP/SMX in some countries. For simple UTIs, children often respond to a three-day course of antibiotics. Women with recurrent simple UTIs may benefit from self-treatment upon occurrence of symptoms with medical follow-up only if the initial treatment fails.

For sexually active women who are not pregnant, screening is recommended in those under 25 and others at risk of infection. Risk factors include a history of chlamydial or other sexually transmitted infection, new or multiple sexual partners, and inconsistent condom use. For pregnant women, guidelines vary: screening women with age or other risk factors is recommended by the U.S. Preventive Services Task Force (USPSTF) (which recommends screening women under 25) and the American Academy of Family Physicians (which recommends screening women aged 25 or younger). The American College of Obstetricians and Gynecologists recommends screening all at risk, while the Centers for Disease Control and Prevention recommend universal screening of pregnant women. The USPSTF acknowledges that in some communities there may be other risk factors for infection, such as ethnicity. Evidence-based recommendations for screening initiation, intervals and termination are currently not possible. For men, the USPSTF concludes evidence is currently insufficient to determine if regular screening of men for chlamydia is beneficial. They recommend regular screening of men who are at increased risk for HIV or syphilis infection.

In the United Kingdom the National Health Service (NHS) aims to:

1. Prevent and control chlamydia infection through early detection and treatment of asymptomatic infection;

2. Reduce onward transmission to sexual partners;

3. Prevent the consequences of untreated infection;

4. Test at least 25 percent of the sexually active under 25 population annually.

5. Retest after treatment.

Even when the PID infection is cured, effects of the infection may be permanent. This makes early identification essential. Treatment resulting in cure is very important in the prevention of damage to the reproductive system. Formation of scar tissue due to one or episodes of PID can lead to tubal blockage, increasing the risk of the inability to get pregnant and long-term pelvic/abdominal pain. Certain occurrences such as a post pelvic operation, the period of time immediately after childbirth (postpartum), miscarriage or abortion increase the risk of acquiring another infection leading to PID.

"Actinomyces" bacteria are generally sensitive to penicillin, which is frequently used to treat actinomycosis. In cases of penicillin allergy, doxycycline is used.

Sulfonamides such as sulfamethoxazole may be used as an alternative regimen at a total daily dosage of 2-4 grams. Response to therapy is slow and may take months.

Hyperbaric oxygen therapy may also be used as an adjunct to conventional therapy when the disease process is refractory to antibiotics and surgical treatment.

Neonatal infection treatment is typically started before the diagnosis of the cause can be confirmed.

Neonatal infection can be prophylactically treated with antibiotics. Maternal treatment with antibiotics is primarily used to protect against group B streptococcus.

Women with a history of HSV, can be treated with antiviral drugs to prevent symptomatic lesions and viral shedding that could infect the infant at birth. The antiviral medications used include acyclovir, penciclovir, valacyclovir, and famciclovir. Only very small amounts of the drug can be detected in the fetus. There are no increases in drug-related abnormalities in the infant that could be attributed to acyclovir. Long-term effects of antiviral medications have not been evaluated for their effects after growth and development of the child occurs. Neutropenia can be a complication of acyclovir treatment of neonatal HSV infection, but is usually transient. Treatment with immunoglobulin therapy has not been proven to be effective.

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.

People with acute pyelonephritis that is accompanied by high fever and leukocytosis are typically admitted to the hospital for intravenous hydration and intravenous antibiotic treatment. Treatment is typically initiated with an intravenous fluoroquinolone, an aminoglycoside, an extended-spectrum penicillin or cephalosporin, or a carbapenem. Combination antibiotic therapy is often used in such situations. The treatment regimen is selected based on local resistance data and the susceptibility profile of the specific infecting organism(s).

During the course of antibiotic treatment, serial white blood cell count and temperature are closely monitored. Typically, the intravenous antibiotics are continued until the person has no fever for at least 24 to 48 hours, then equivalent antibiotics by mouth can be given for a total of 2–week duration of treatment. Intravenous fluids may be administered to compensate for the reduced oral intake, insensible losses (due to the raised temperature) and vasodilation and to optimize urine output. Percutaneous nephrostomy or ureteral stent placement may be indicated to relieve obstruction caused by a stone. Children with acute pyelonephritis can be treated effectively with oral antibiotics (cefixime, ceftibuten and amoxicillin/clavulanic acid) or with short courses (2 to 4 days) of intravenous therapy followed by oral therapy. If intravenous therapy is chosen, single daily dosing with aminoglycosides is safe and effective.

Treatment of xanthogranulomatous pyelonephritis involves antibiotics as well as surgery. Removal of the kidney is the best surgical treatment in the overwhelming majority of cases, although polar resection (partial nephrectomy) has been effective for some people with localized disease. Watchful waiting with serial imaging may be appropriate in rare circumstances.

A number of medications can be used to treat this disorder. Alpha blockers and/or antibiotics appear to be the most effective with NSAIDs such as ibuprofen providing lesser benefit.

- Treatment with antibiotics is controversial. Some have found benefits in symptoms while others have questioned the utility of a trial of antibiotics. Antibiotics are known to have anti-inflammatory properties and this has been suggested as an explanation for their partial efficacy in treating CPPS. Antibiotics such as fluoroquinolones, tetracyclines, and macrolides have direct anti-inflammatory properties in the absence of infection, blocking inflammatory chemical signals (cytokines) such as interleukin-1 (IL-1), interleukin-8 and tumor necrosis factor (TNF), which coincidentally are the same cytokines found to be elevated in the semen and EPS of men with chronic prostatitis.

- The effectiveness of alpha blockers (tamsulosin, alfuzosin) is questionable in men with CPPS. A 2006 meta-analysis found that they are moderately beneficial when the duration of therapy was at least 3 months.

- An estrogen reabsorption inhibitor such as mepartricin improves voiding, reduces urological pain and improves quality of life in patients with chronic non-bacterial prostatitis.

- Therapies that have not been properly evaluated in clinical trials although there is supportive anecdotal evidence include gabapentin, benzodiazepines, and amitriptyline.

In people who do not require hospitalization and live in an area where there is a low prevalence of antibiotic-resistant bacteria, an fluoroquinolone by mouth such as ciprofloxacin or levofloxacin is an appropriate initial choice for therapy. In areas where there is a higher prevalence of fluoroquinolone resistance, it is useful to initiate treatment with a single intravenous dose of a long-acting antibiotic such as ceftriaxone or an aminoglycoside, and then continuing treatment with a fluoroquinolone. Oral trimethoprim/sulfamethoxazole is an appropriate choice for therapy if the bacteria is known to be susceptible. If trimethoprim/sulfamethoxazole is used when the susceptibility is not known, it is useful to initiate treatment with a single intravenous dose of a long-acting antibiotic such as ceftriaxone or an aminoglycoside. Oral beta-lactam antibiotics are less effective than other available agents for treatment of pyelonephritis. Improvement is expected in 48 to 72 hours.

Some vertically transmitted infections, such as toxoplasmosis and syphilis, can be effectively treated with antibiotics if the mother is diagnosed early in her pregnancy. Many viral vertically transmitted infections have no effective treatment, but some, notably rubella and varicella-zoster, can be prevented by vaccinating the mother prior to pregnancy.

If the mother has active herpes simplex (as may be suggested by a pap test), delivery by Caesarean section can prevent the newborn from contact, and consequent infection, with this virus.

IgG antibody may play crucial role in prevention of intrauterine infections and extensive research is going on for developing IgG-based therapies for treatment and vaccination.

Transurethral needle ablation of the prostate (TUNA) has been shown to be ineffective in trials.

In a small minority of cases of urethral syndrome, treatment with antibiotics is effective, which indicates that in some cases it may be caused by bacterial infection which does not show up in either urinalysis or urine culture. For chronic urethral syndrome, a long term, low-dose antibiotic treatment is given on a continuous basis or after intercourse each time if intercourse appears to trigger symptoms.

As low oestrogen may also be considered a source for urethral syndrome, hormone replacement therapy, and oral contraceptive pill (birth-control pills) containing oestrogen are also used to treat the symptoms of this condition in women.

Antibiotics have been used to prevent and treat these infections however the misuse of antibiotics is a serious problem for global health. It is recommended that guidelines be followed which outline when it is appropriate to give antibiotics and which antibiotics are most effective.

Atelectasis: mild to moderate fever, no changes or mild rales on chest auscultation.

Management: pulmonary exercises, ambulation (deep breathing and walking)

Urinary tract infection : high fever, malaise, costovertebral tenderness, positive urine culture.

Management: antibiotics as per culture sensitivity (cephalosporine).

Endometritis: moderate fever, exquisite uterine tenderness, minimal abdominal findings.

Management: multiple agent IV antibiotics to cover polymicrobial organisms: clindamycin, gentamicin, addition of ampicillin if no response, no cultures are necessary.

Wound infection: persistent spiking fever despite antibiotics, wound erythema or fluctuance, wound drainage.

Management: antibiotics for cellulitis, open and drain wound, saline-soaked packing twice a day, secondary closure.

Septic pelvic thrombophlebitis: persistent wide fever swings despite antibiotics, usually normal abdominal or pelvic exams.

Management: IV heparin for 7–10 days at rates sufficient to prolong the PTT to double the baseline values.

Mastitis: unilateral, localized erythema, edema, tenderness.

Management: antibiotics for cellulitis, open and drain abscess if present.