Ear infections

Highlights

Middle ear (otitis media) infections are very common in young children. They include:

Preventing colds and influenza ("flu") is the best way to prevent ear infections. Make sure children wash their hands frequently and receive an influenza vaccine annually and the recommended series of pneumococcal vaccinations. No one should smoke around children, since exposure to second-hand tobacco smoke can increase the risk for middle ear infections. Breastfeeding for a baby's first 6 months can help protect against ear infections.

Introduction

The ear is the organ of hearing and balance. It has 3 parts: the outer, middle, and inner ear:

Ear anatomy

The ear consists of external, middle, and inner structures. The eardrum and the three tiny bones conduct sound from the eardrum to the cochlea.

Acute Otitis Media (AOM)

An inflammation in the middle ear is known as "otitis media." AOM is a middle ear infection caused by bacteria that has traveled to the middle ear from fluid buildup in the Eustachian tube. AOM may develop during or after a cold or the flu. With AOM:

Otitis Media with Effusion (OME)

OME occurs when fluid, called an effusion, becomes trapped behind the eardrum in one or both ears. In chronic and severe cases, the fluid is very sticky and is commonly called "glue ear." With OME:

Chronic Otitis Media

This condition refers to persistent perforation or hole in the tympanic membrane. It is called chronic suppurative otitis media when there is persistent pus-like drainage inflammation in the middle ear or mastoids (the rounded bone just behind the ear). There may also be a chronic rupture of the eardrum with either ongoing drainage that is not infected or a dry eardrum with a perforation but no drainage or infection.

Other chronic changes may result from severe acute infections, recurrent infections, or a chronic infection. These changes include bone erosion, erosion and changes in the ossicular bones behind the eardrum, or scarring of the eardrum and middle ear compartment. These problems often lead to chronic hearing loss.

Swimmer's Ear (Acute Otitis Externa)

Acute otitis externa is an inflammation or infection of the outer ear and ear canal. It can be triggered by water that gets trapped in the ear. The trapped water can cause bacteria and fungi to breed. Otitis externa can also be precipitated by overly aggressively scratching or cleaning of ears or when an object gets stuck in the ears.

Otitis externa should be treated with topical antibiotics, which will cure the infection and help relieve pain. With eardrops, most cases will clear up within 2 to 3 days. If the condition persists, the doctor will need to evaluate and rule out other possible causes.

Causes

Acute otitis media (middle ear infection) is usually due to a combination of factors that increase susceptibility to bacterial and viral infections in the middle ear.

The primary setting for middle ear infections is in a child's Eustachian tube, which runs from the middle ear to the nose and upper throat. The Eustachian tube is shorter and narrower in children than adults, and more vulnerable to blockage. It is also more horizontal in younger children and therefore does not drain as well. Children with abnormally short and relatively horizontal Eustachian tubes are at particular risk for ear infections.

Bacteria

Many bacteria normally thrive in the passages of the nose and throat. Most are not harmful. However, certain types of bacteria commonly cause ear infections. They are:

Viruses

Viruses play an important role in many ear infections, and can set the stage for bacterial infections. Rhinoviruses are the common viruses that cause colds. While rhinoviruses themselves do not cause ear infections, if a cold does occur the virus can cause the membranes along the walls of the inner ear passages to swell and obstruct the airways. If this inflammation blocks the narrow Eustachian tube, the middle ear may not drain properly. Fluid builds up and becomes a breeding ground for bacteria and subsequent infection.

Other viruses, such as respiratory syncytial virus (RSV, a virus responsible for childhood respiratory infections) and influenza (flu), can be the actual causes of some ear infections. Nearly a third of infants and toddlers with upper respiratory infections go on to develop acute otitis media.

Evidence suggests that both viruses and bacteria play a role in ear infections. Viruses can increase middle ear inflammation and interfere with antibiotics' effectiveness in treating bacterial causes of ear infections. HIV or other viruses that weaken the immune system can increase the risk for ear infections.

Congenital structural abnormalities, such as cleft palate, increase the risk for ear infections. Genetic conditions, such as Kartagener's syndrome in which the cilia (hair-like structures) in the ear are immobile and cause fluid buildup, also increase the risk. Children with Down syndrome or fetal alcohol syndrome may also be at increased risk due to anatomical abnormalities.

Risk Factors

In the United States, ear infections are the most common reason why children see the doctor.

Acute Otitis Media (AOM)

AOM generally affects children ages 6 to 18 months. The earlier a child has a first ear infection, the more susceptible they are to recurrent episodes. About two-thirds of children will have a least one attack of AOM by age 3, and a third of these children will have at least three episodes. Boys are more likely to have infections than girls.

As children grow, the structures in their ears enlarge and their immune systems become stronger. By age 16 months, the risk for recurrent infections rapidly decreases. After age 5, most children outgrow their susceptibility to ear infections.

Otitis Media with Effusion

OME is very common in children age 6 months to 4 years, with about 90% of children having OME at some point. More than half of children have OME by age 2.

Ear infections are more likely to occur in the fall and winter. The following conditions also put children at higher risk for ear infection:

Complications

Severe cases of recurrent acute otitis media (AOM) or persistent otitis media with effusion (OME) may impair hearing for a period of time. But the hearing loss is not substantial or permanent for most children.

Hearing loss in children may temporarily slow down language development and reading skills. However, uncomplicated chronic middle ear effusion generally poses no danger for developmental delays in otherwise healthy children.

Rarely, patients with chronic otitis media develop involvement of the inner ear. In these situations hearing loss can potentially be permanent. Most of these patients will also have problems with vertigo (dizziness).

Serious complications or permanent physical injuries from ear infections are very uncommon, but may include:

Before the introduction of antibiotics, mastoiditis (an infection in the bones located in the skull region behind the ears) was a serious, although rare, complication of otitis media. The condition is difficult to treat and requires intravenous antibiotics and drainage procedures. Surgery may be necessary.

If pain and fever persist in spite of antibiotic treatment of otitis media, the doctor should check for mastoiditis. Most cases of mastoiditis are generally not associated with ear infections.

Mastoiditis

If an infection of the mastoid air cells cannot be controlled with antibiotics, surgery may be needed.

Meningitis

In rare cases, bacteria from a severe ear infection can spread to the tissues surrounding the brain.

Facial Paralysis

Very rarely, a child with acute otitis media may develop facial paralysis, which is temporary and usually relieved by antibiotics or possibly drainage surgery. Facial paralysis may also occur in patients with chronic otitis media and a cholesteatoma (tissue in the middle ear). Surgery is usually needed to correct this condition.

Symptoms

You should contact the pediatrician if your child has any of the following signs of ear infection:

Ear pain is the most common symptom of ear infections. The ear pain associated with acute otitis media usually comes on very suddenly.

Babies and young children who haven't yet learned to speak may express ear pain in various ways including:

Other symptoms associated with ear infections include:

If the ear infection is severe, the tympanic membrane may rupture, causing the pus to drain from the ear. (This usually brings relief from pain.) Pus in the ear may cause hearing loss in some children.

OME may have no symptoms at all. Some hearing loss may occur, but it is often fluctuating and hard to detect. The only sign to a parent that the condition exists may be when a child complains of "plugged up" hearing. Other symptoms can include loud talking, not responding to verbal commands, and turning up the television or radio.

Older children with OME may have difficulty targeting specific sounds in a noisy room. In such cases, some parents or teachers may attribute their behavior to lack of attention or even to an attention deficit disorder. Older children and adults may also notice a sense of fullness in the ear. OME is often diagnosed during a regular pediatric visit.

Diagnosis

Symptoms are not reliable in themselves for diagnosing ear infections. Ear pain, ear tugging, irritability, fussiness, and similar symptoms may be due to ear infections or they may be caused by unrelated health conditions (colds, other infections, teething).

Specific physical signs that a doctor must identify to diagnose acute otitis media (AOM). They include:

AOM (fluid and infection) is often difficult to differentiate from OME (fluid without infection). It is important for a doctor to make this distinction because OME does not require antibiotic treatment. This is why the new guidelines recommend that doctors use a pneumatic otoscope during the physical exam to get a clearer picture of the eardrum's appearance.

During an ear examination, the doctor will first remove any ear wax (called cerumen) in order to get a clear view of the eardrum. The doctor will then use a procedure called pneumatic otoscopy:

Otoscope examination

An otoscope is a tool that shines a beam of light to help visualize and examine the condition of the ear canal and eardrum. Examining the ear can reveal the cause of symptoms such as an earache, the ear feeling full, or hearing loss.

The pneumatic otoscope is considered the standard tool for diagnosis of middle ear infections. Another procedure that is used is called tympanometry:

Neither tympanometry nor reflectometry are substitutes for the pneumatic otoscope, which allows a direct view of the middle ear.

Parents can also use a sonar-like device, such as the EarCheck Monitor, to determine if there is fluid in their child's middle ear. EarCheck uses acoustic reflectometry technology, which bounces sound waves off the eardrum to assess mobility. When fluid is present behind the middle ear (a symptom of AOM and OME), the eardrum will not be as mobile. The device works like an ear thermometer and is painless. Results indicate the likelihood of the presence of fluid and may help patients decide whether they need to contact their child's doctor.

On rare occasions the doctor may need to draw fluid from the ear using a needle for identifying specific bacteria, a procedure called tympanocentesis. This procedure can also relieve severe ear pain. It is most often performed by an ear, nose, and throat (ENT) specialist, and usually only in severe or recurrent cases. In most cases, tympanocentesis is not necessary in order to obtain an accurate enough diagnosis for effective treatment.

Hearing tests performed by an audiologist are usually recommended for children with persistent otitis media with effusion. A hearing loss below 20 decibels usually indicates problems.

Determining Impaired Hearing in Infants and Small Children

Unfortunately, it is very difficult to test children under 2 years old for hearing problems. One way to determine hearing problems in infants is to gauge the baby's language development:

If a child's progress is significantly delayed beyond these times, a parent should suspect possible hearing problems.

Determining Impaired Hearing in Older Children

Hearing loss in older children may be detected by the following behaviors:

Prevention

The best way to prevent ear infections is to prevent colds and flu. The American Academy of Pediatricians recommends that all children receive the pneumococcal vaccine (PCV13) and an annual flu shot.

The American Academy of Pediatrics (AAP) and the U.S. Centers for Disease Control (CDC) recommend annual influenza vaccination for all children over 6 months of age. Preventing the flu (influenza) is an important protective measure against ear infections.

Flu vaccines are typically given by injection, usually between October and December. The earlier your child receives the vaccine, the earlier the immunity to the flu will take effect. It usually takes about 2 weeks for antibodies to the influenza virus to develop. These antibodies provide protection against the virus.

An intranasal vaccine called FluMist is approved for children ages 2 years and older. FluMist is made from a live but weakened influenza virus; flu shots use inactivated (not live) viruses. Children younger than 2 years old, and children younger than age 5 who have asthma or recurrent wheezing, should not receive FluMist.

Side effects of the flu shot are generally mild but may include soreness at the injection site, low-grade fever, or body aches. These side effects usually go away on their own within a few days.

Side effects of the nasal flu vaccine in children can include runny nose, wheezing, vomiting, muscle aches, and fever.

The pneumococcal conjugate vaccine (PCV13) protects against 13 of the most important strains of S. pneumoniae that cause pneumococcal meningitis, pneumococcal pneumonia, and other respiratory infections. It also protects against many of the bacteria that cause middle ear infections.

PCV13 is specifically approved to help prevent invasive pneumococcal disease and otitis media. The recommended schedule of pneumococcal immunization is four doses, one each given at 2, 4, 6, and 12 to 15 months of age.

Side effects of the pneumococcal vaccine are usually mild, but may include:

Cold and flu viruses spread when an infected person coughs or sneezes. These viruses can also be transmitted by shaking hands. Everyone should always wash their hands before eating and after going outside. Ordinary soap is sufficient. Waterless hand cleansers that contain an alcohol-based gel are also effective. Antibacterial soaps add little protection, particularly against viruses. Wiping surfaces with a solution that contains one part bleach to 10 parts water is very effective in killing viruses.

Breastfeeding offers protection against many early infections, including ear infections. Mother's milk provides immune factors that help protect the child from infections. Also, infants are held during breastfeeding in a position that allows the Eustachian tubes to function well.

If possible, new mothers should breastfeed their infants for at least 4 to 6 months. According to the American Academy of Pediatrics, exclusively breastfeeding for a baby's first 6 months helps to prevent ear and other respiratory infections. For bottle-fed babies, to improve protection do not lay the baby down with the bottle ("bottle propping"). Hold the infant in the same way you would to breastfeed.

No one should smoke around children. Studies indicate that children who live with smokers have a significantly increased risk for ear infections.

Treatment

Most cases of AOM clear up on their own within a week and do not require antibiotic treatment. (Antibiotics are necessary for children with special health concerns, and infants younger than 6 months.) Doctors often recommend a "watchful waiting" period for the first 48 to 72 hours after symptoms appear, to see if ear pain and other symptoms resolve on their own.

For antibiotic treatment, the latest recommendations are:

Ear tube (tympanostomy) insertion are an option for children who have had at least 3 occurrences of AOM in 6 months or 4 episodes in a year. However, newer guidelines strongly advise that tympanostomy tube surgery should be used only for children who have middle-ear effusion (fluid behind the eardrum) and not for children with frequent AOM infections.

Parents can help reduce risks for ear infections by breastfeeding for the baby's first 6 months, avoiding bottle propping, avoiding exposure to second-hand tobacco smoke, and making sure their children receive vaccinations for pneumococcal disease and influenza.

Otitis media with effusion (OME) is fluid behind the middle ear (eardrum). It usually resolves on its own without treatment, especially when it follows an acute ear infection. Antibiotics are not helpful for most cases of OME.

Clinical practice guidelines for OME recommend the following treatments:

Children with persistent OME lasting longer than 3 months should get a hearing test. Children may be candidates for ear tube (tympanostomy) insertion surgery if they have:

Insertion of tympanostomy tubes into the eardrum is the first choice for surgical intervention. Adenoidectomy (removal of adenoids) plus myringotomy (removal of fluid), with or without tube insertion, is sometimes recommended as a repeat surgical procedure. (Myringotomy alone is not recommended for OME treatment. Adenoidectomy is not recommended as an initial procedure unless some other condition (chronic sinusitis, nasal obstruction, adenoiditis) is present.

Tonsillectomy (removal of tonsils) is not recommended for OME treatment.

Home Remedies

Before antibiotics, parents used home remedies to treat the pain of ear infections. Now, with current concern over antibiotic overuse, many of these simple remedies are again popular:

A number of pain relievers are available to help relieve symptoms:

Note: Aspirin and aspirin-containing products are not recommended for children or adolescents. Reye syndrome, a very serious condition, is associated with aspirin use in children who have chickenpox or flu.

Decongestants (pills or nasal sprays or drops), antihistamines, or combination products are not recommended for AOM or OME.

Recent research has questioned the general safety of cough and cold products for children. They are currently banned for use in children under age 4 years. The American College of Chest Physicians recommends against the use of nonprescription cough and cold medicines in children age 14 years and younger.

A simple technique called the Valsalva's maneuver is useful in opening the Eustachian tubes and providing occasional relief from the chronic stuffy feeling that accompanies otitis media with effusion. It may also be useful for unplugging ears during air travel descent. It works as follows:

Do not use this technique if an infection is present.

Swimming can pose specific risks for children with current ear infections or previous surgery. Water pollutants or chemicals may worsen the infection, and underwater swimming causes pressure changes that can cause pain. The following precautions should be taken:

Medications

Pain relievers such as ibuprofen or acetaminophen are the main drug treatments used for ear infections. Doctors want to avoid prescribing antibiotics unless they are absolutely needed. Your child's doctor may recommend watchful waiting for the first 48 to 72 hours after symptoms appear, to see if ear pain and other symptoms resolve on their own.

The latest guidelines from the American Academy of Pediatrics recommend antibiotics for the following otherwise healthy children who have acute otitis media:

If a child needs antibiotics for acute otitis media, the drugs should be taken for the following periods of time:

Parents should be sure their child finishes the entire course of therapy.

Your child's symptoms, including fever, should improve within 48 to 72 hours after beginning antibiotics. If symptoms do not improve it may be because a virus is present or the bacteria causing the ear infection is resistant to the prescribed antibiotic. A different antibiotic may be needed.

In some children whose treatment is successful, fluid will still remain in the middle ear for weeks or months, even after the infection has resolved. During that period, children may have some hearing problems, but eventually the fluid almost always drains away.

If your child fails to improve and middle ear fluid remains, your doctor may recommend consultation with an ear, nose, and throat specialist (otolaryngologist). This specialist may perform a tympanocentesis procedure in which fluid is drawn from the ear and examined for specific bacterial organisms. But this is reserved for severe cases.

Amoxicillin, a penicillin type of antibiotic, is generally recommended for first-line treatment of AOM. The combination drug amoxicillin-clavulanate is an alternative option. Children who are allergic to penicillin drugs will be prescribed a different antibiotic.

Children who do not respond within 48 to 72 hours to initial treatment with amoxicillin may be given a course of amoxicillin-clavulanate or ceftriaxone. Alternative treatments are ceftriaxone or clindamycin, which may also be accompanied by a different cephalosporin antibiotic.

Surgery

Tympanostomy surgery involves the insertion of a tiny tube to prevent fluid from building up in the middle ear. These ear tubes (also called tympanostomy tubes) allow air to flow into the middle ear and help prevent infections caused by fluid accumulation.

The procedure involves:

Ear tube insertion - Series

Postoperative Effects

Tympanostomy is a simple procedure, and the child almost never has to spend the night in the hospital. Acetaminophen (Tylenol, generic) or ibuprofen (Advil, generic) is sufficient for any postoperative pain in most children. However, some children may need codeine or other powerful pain relievers.

Generally, the tubes stay in the eardrum for 6 to 12 months before coming out on their own. Less commonly, long-term tubes are implanted that need to be surgically removed. Children with ear tubes can usually swim and bathe normally, and do not need to wear earplugs.

Complications

Otorrhea, drainage of secretion from the ear, is the most common complication after surgery and can be persistent in some children. This discharge can be treated with antibiotic eardrops.

More serious complications from the operation are very uncommon, but may include:

Success Rates

Hearing is almost always restored following tympanostomy. Failure to achieve normal or near-normal hearing is usually due to complicated conditions, such as preexisting ear problems or persistent OME in children who have had previous multiple tympanostomies. Persistent fluid is the main reason for continued impaired hearing. Only a small percentage of hearing loss cases can be attributed to complications of the operation itself.

Follow-Up

Eventually, the tubes fall out as the hole in the eardrum closes. This may happen after several months or more than a year later. It is painless. In fact, the patient and parents may not even be aware that the tubes are out.

About 20% to 50% of children may have OME relapse and need additional surgery that involves adenoidectomy and myringotomy. Tube reinsertion may be recommended for children younger than 4 years of age.

Myringotomy is used to drain the fluid and may be used (with or without ear tube insertion) in combination with adenoidectomy as a repeat surgical procedure if initial tympanostomy is not successful. It is not effective as a sole surgical procedure. Myringotomy involves the following steps:

Adenoids are collections of spongy lymph tissue in the back of the throat, similar to the tonsils. Removal of the adenoids, called adenoidectomy, is usually considered only for OME if a pre-existing condition exists, such as chronic sinusitis, nasal obstruction, or chronic adenoiditis (inflammation of the adenoids). Unless these conditions exist, adenoidectomy is not recommended for treatment of OME.

Adenoidectomy plus myringotomy (removal of fluid) may be performed if an initial tympanostomy (tube insertion) procedure is unsuccessful in resolving OME. This combination procedure works best in children ages 4 years or older. Tube insertion alone is recommended for children under 4 years of age. It is not necessary to perform an adenoidectomy along with tube insertion for children under 4 years of age.

Adenoids

Laser-assisted myringotomy is a technique that is being investigated as an alternative to conventional tympanostomy and myringotomy. At present, there is not enough evidence to say whether it is as good as ear tubes, the standard procedure. Some clinical trials have suggested that the success rate for laser-assisted myringotomy is half that of standard tympanostomy/myringotomy. Many insurance companies consider laser-assisted myringotomy to be an investigational procedure and will not pay for it.

Resources

References

Casselbrandt ML, Mandel EM. Acute otitis media and otitis media with effusion. In: Flint PW, Haughey BH, Lund V, et al, eds. Cummings Otolaryngology. 6th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 195.

Chole RA. Chronic otitis media, mastoiditis, and petrositis. In: Flint PW, Haughey BH, Lund V, et al, eds. Cummings Otolaryngology. 6th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 139.

Gulani A, Sachdev HS. Zinc supplements for preventing otitis media. Cochrane Database Syst Rev. 2014;29(6):CD006639. PMID: 24974096 www.ncbi.nlm.nih.gov/pubmed/24974096.

Harris AS, Elhassan HA, Flook EP. Why are ototopical aminoglycosides still first-line therapy for chronic suppurative otitis media? A systematic review and discussion of aminoglycosides versus quinolones. J Laryngol Otol. 2016;130(1):2-7. PMID: 26584651 www.ncbi.nlm.nih.gov/pubmed/26584651.

Hersh AL, Jackson MA, Hicks LA; American Academy of Pediatrics Committee on Infectious Diseases. Principles of judicious antibiotic prescribing for upper respiratory tract infections in pediatrics. Pediatrics. 2013;132(6):1146-1154. PMID: 24249823 www.ncbi.nlm.nih.gov/pubmed/24249823.

Klein JO. Otitis externa, otitis media,and mastoiditis. Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, Updated Edition. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 62.

Kerschner JE, Preciado D. Otitis Media. In: Kliegman RM, Stanton BF, St Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier; 2016:chap 640.

Robinson CL; Advisory Committee on Immunization Practices (ACIP), ACIP Child/Adolescent Immunization Work Group. Advisory committee on immunization practices recommended immunization schedules for persons aged 0 through 18 years -- United States, 2016. Am J Transplant. 2016;16(6):1928-1929. PMID: 27197897 www.ncbi.nlm.nih.gov/pubmed/27197897.

Rosenfeld RM, Schwartz SR, Cannon CR, et al. Clinical practice guideline: acute otitis externa. Otolaryngol Head Neck Surg. 2014;150(1 Suppl):S1-S24. PMID: 24491310 www.ncbi.nlm.nih.gov/pubmed/24491310.

Rosenfeld RM, Schwartz SR, Pynnonen MA, et al. Clinical practice guideline: tympanostomy tubes in children. Otolaryngol Head Neck Surg. 2013;149(1 Suppl):S1-S35. PMID: 23818543 www.ncbi.nlm.nih.gov/pubmed/23818543.

Siddiq S, Grainger J. The diagnosis and management of acute otitis media: American Academy of Pediatrics Guidelines 2013. Arch Dis Child Educ Pract Ed. 2015;100(4):193-197.PMID: 25395494 www.ncbi.nlm.nih.gov/pubmed/25395494.

Tapiainen T, Kujala T, Renko M, et al. Effect of antimicrobial treatment of acute otitis media on the daily disappearance of middle ear effusion: a placebo-controlled trial. JAMA Pediatr. 2014;168(7):635-641.PMID: 24797294 www.ncbi.nlm.nih.gov/pubmed/24797294.

van Dongen TM, van der Heijden GJ, Venekamp RP, Rovers MM, Schilder AG. A trial of treatment for acute otorrhea in children with tympanostomy tubes. N Engl J Med. 2014;370(8):723-733. PMID: 24552319 www.ncbi.nlm.nih.gov/pubmed/24552319.

Venekamp RP, Sanders SL, Glasziou PP, Del Mar CB, Rovers MM. Antibiotics for acute otitis media in children. Cochrane Database Syst Rev. 2015;(6):CD000219. PMID: 26099233 www.ncbi.nlm.nih.gov/pubmed/26099233.

Wallace IF, Berkman ND, Lohr KN, Harrison MF, Kimple AJ, Steiner MJ. Surgical treatments for otitis media with effusion: a systematic review. Pediatrics. 2014;133(2):296-311.PMID: 24394689 www.ncbi.nlm.nih.gov/pubmed/24394689.



Review Date: 8/31/2016
Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
adam.com
A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.