Is Paraphimosis an Emergency? What Happens at the Hospital and How It Is Reduced

It is late, the house is quiet, and a man stands in the bathroom looking at something that was fine an hour ago. He pulled the foreskin back to wash, or a nurse retracted it earlier for a catheter, and now it will not come forward. The head of the penis is swelling. The skin behind it is puffing into a doughnut. Every attempt to fix it makes it hurt more, and a small voice is asking whether this can wait until morning.

It cannot. This is the paraphimosis emergency that urologists and emergency clinicians train for, and the reason they take it seriously is not squeamishness but plumbing. A band of tissue is acting like a tourniquet on the most richly supplied organ in the body.

What follows is an honest account of what happens once you walk through the hospital doors, how the foreskin is actually put back, and what the days afterward look like.

Is paraphimosis an emergency, or can it wait?

Paraphimosis sits on the short list of genital problems that clinicians want to see the same day. The reason is mechanical. The foreskin, once pulled back over the glans (the head of the penis), normally slides forward again without effort. In paraphimosis it gets caught behind the glans and a ring of tissue tightens around the shaft. That ring squeezes the veins and lymph channels first, so fluid drains out of the glans more slowly than blood arrives. The glans swells, the ring becomes relatively tighter, and the swelling worsens in a loop that does not break on its own.

The NIH StatPearls review describes paraphimosis as a true urological emergency because, left long enough, the constriction can progress from venous congestion to arterial compromise, meaning the tissue beyond the ring stops receiving oxygenated blood. That end point is rare, and most people reach care well before it, but the trajectory is the point. Pain and swelling that are tolerable at hour one are usually worse at hour four.

MedlinePlus puts it plainly: paraphimosis is a medical emergency that needs prompt treatment, and the foreskin should be returned to its normal position as soon as possible. Waiting to see if it settles is the one strategy that reliably fails, because the swelling itself is what keeps the foreskin trapped.

None of this means panic. It means picking up the phone or the car keys now rather than setting an alarm. An urgent care clinic, an emergency department, or a call to a urology on-call line are all reasonable first moves; the choice depends on what is open and how far away it is. Whichever door you use, the aim is the same: get the foreskin back where it belongs within hours, not days.

Paraphimosis vs phimosis: two foreskin problems that get confused

People often arrive at the hospital saying they have phimosis when they mean paraphimosis, and the two are close to opposites. Phimosis is a foreskin that is too tight to be pulled back over the glans. Paraphimosis is a foreskin that has been pulled back and now cannot be brought forward. The first is a chronic, often painless condition that can be managed over weeks or months. The second is acute, painful, and cannot be scheduled for a later appointment.

The NHS groups both under the heading of tight foreskin and notes that phimosis in young boys is usually normal and resolves as the child grows, while paraphimosis at any age needs urgent attention. That framing is useful because it explains why the same anatomy produces such different levels of urgency. In phimosis the foreskin sits forward, covering the glans, and blood flow is not affected. In paraphimosis the foreskin sits behind the glans, and its tight opening, called the preputial ring, becomes a constricting band.

There is a link between the two. A mildly tight foreskin that can just about be retracted with effort is the one most likely to get stuck once the glans swells even slightly. The NIH review lists a pre-existing narrow preputial ring as one of the main predisposing factors. So someone who has struggled for years to retract fully, and finally manages it during washing or intimacy, is exactly the person at risk.

Knowing which word applies matters when you call for advice. Saying “my foreskin is stuck behind the head and it is swelling” tells a triage nurse everything needed to prioritize you correctly. Saying “I have a tight foreskin” may be filed as routine.

How paraphimosis happens: the mechanism behind the swelling

Think of a rubber band slipped over a finger and left there. Nothing dramatic happens in the first minute. Then the fingertip turns pink, then dusky, then it throbs. The band did not change; the tissue beyond it did, because blood kept arriving under arterial pressure while the low-pressure veins beneath the band were pinched shut. Paraphimosis works the same way, with the foreskin’s opening as the band and the glans as the fingertip.

Once the ring is behind the glans, the sequence described in the NIH StatPearls review unfolds in a predictable order. Venous and lymphatic return are compressed first. Fluid leaks from tiny vessels into the surrounding tissue, producing edema, the medical word for swelling from trapped fluid. The foreskin itself, now sitting behind the glans, also swells into the soft, ring-shaped collar that clinicians recognize immediately. As both the glans and the collar enlarge, the constriction tightens relative to what it is squeezing, and the loop feeds itself.

Arterial flow is the last thing to go, because arteries are muscular and carry blood at higher pressure. That is why tissue death is uncommon and why clinicians have a window of hours to act. It is also why color changes matter so much: a glans that is pink and swollen is congested; one that is turning blue, purple, or gray is signaling that the window is narrowing.

Common triggers, according to MedlinePlus and the NIH review, include forgetting to replace the foreskin after washing, sexual activity, medical procedures such as urinary catheter insertion or a genital exam, and piercings. In each case the foreskin was retracted, and nobody pulled it forward before the swelling began.

Should I go to the ER for paraphimosis?

Yes, or to whatever urgent, walk-in medical setting can see you within hours. The question people are really asking is whether this is an embarrassing inconvenience or a genuine hazard, and the honest answer is that it is both, and the hazard wins.

An emergency department is the right choice if the swelling is significant, the color of the glans is changing, the pain is severe, you cannot pass urine, or the foreskin has been trapped for several hours already. Emergency clinicians see paraphimosis regularly, have local anesthetic and sedation available, and can call a urologist if the first attempts do not work. An urgent care clinic can manage many straightforward cases, but not every clinic will attempt reduction, and being redirected costs time.

If the problem started during a hospital stay, for example after a catheter was placed, tell the nursing staff at once rather than waiting for the next round. The NIH review specifically flags healthcare-related retraction as a cause, and the fix is far easier in the first hour than the fifth.

What you should not do is book a routine appointment for later in the week, take a painkiller and go to bed, or wait to see whether it improves. MedlinePlus advises seeking care right away, and the NHS lists a foreskin that will not go back as a reason to get urgent medical help.

People sometimes delay because they fear the treatment will be worse than the problem. It rarely is. Most reductions are done in minutes with cold, gentle pressure and local numbing, and the relief is immediate. The longer the delay, the more likely the simpler methods fail and a small surgical step becomes necessary.

What is mild paraphimosis, and is it still urgent?

The phrase “mild paraphimosis” appears in search boxes far more often than in textbooks. Clinically it usually describes an early case: the foreskin is stuck behind the glans, there is some swelling and discomfort, but the glans is still pink, urine passes normally, and it has only been a short while. That picture is real, and it is also the one most likely to respond to the simplest reduction techniques.

What “mild” does not mean is “can wait.” The mechanism does not have a gentle version that stops on its own. The NIH StatPearls review describes the condition as progressive; a mild case is a severe case with less time elapsed. The swelling that makes reduction easy at hour one is the same swelling that makes it difficult at hour six.

There is one situation in which people mistake something else for mild paraphimosis. A foreskin that is retracted, slightly snug, but slides forward again with a gentle pull is not paraphimosis at all, just a tight foreskin that has been fully retracted. If it comes forward and stays forward, and the swelling settles quickly, that is reassuring. If it will not budge, or comes forward only to slip back behind the glans, treat it as the emergency it is.

Children deserve a special mention. Paraphimosis in a boy usually happens because a caregiver or the child pulled a foreskin back that was not yet ready to retract. The NHS is clear that a young boy’s foreskin should never be forced. If it becomes stuck, the same urgency applies, and the pediatric team will focus on comfort, distraction, and a calm environment before attempting reduction.

What happens at the hospital: triage, examination and the first hour

At the desk you will be asked what the problem is, and the triage nurse will assign a priority. Say the word paraphimosis if you know it, or describe it directly. Genital complaints are handled discreetly; you will be taken to a private room or curtained bay rather than examined in a corridor.

A clinician will ask a short set of questions: when the foreskin became stuck, what you were doing at the time, whether you have had trouble retracting it before, whether you have a catheter, whether you can urinate, and whether you have conditions such as diabetes that affect healing and circulation. The examination itself takes seconds. The diagnosis is made by looking, according to the NIH StatPearls review; no scans or blood tests are needed to confirm it, although a bedside check of the glans color and sensation helps judge how urgent things are.

Pain relief comes next. Depending on the setting and how uncomfortable you are, this may involve a numbing gel applied to the skin, an injection of local anesthetic at the base of the penis (a penile block, which numbs the whole organ without putting you to sleep), or, for children and very distressed adults, light sedation. Which option is chosen is a decision for the treating clinician based on your age, pain level and medical history.

Then the reduction begins. Most first attempts happen right there in the emergency department, often within the first hour of arrival. If the clinician is not confident or the initial method fails, urology is called. Being transferred to a specialist is not a sign that something has gone wrong; it is the normal escalation pathway written into most hospital protocols.

How paraphimosis reduction works, step by step

Paraphimosis reduction means returning the foreskin to its normal position over the glans. The core idea is simple: shrink the swollen glans and collar until the tight ring can slide forward over them. Almost every technique is a variation on that theme.

The first step is reducing edema. Clinicians commonly wrap the penis in a cold compress or ice pack (never ice directly on skin) for several minutes. Cold narrows small vessels and slows fluid leaking into the tissue. The NIH StatPearls review also describes firm, steady compression, in which the clinician wraps the glans and swollen foreskin in gauze or an elastic bandage and squeezes for several minutes to push trapped fluid back toward the body. Some emergency departments use osmotic methods, placing granulated sugar or a sugar-soaked dressing against the swollen tissue to draw fluid out by osmosis, though this takes longer and is often used when quick methods have not worked.

Once the swelling has eased, the manual reduction itself is a coordinated push and pull. The clinician places both thumbs on the glans and wraps the index and middle fingers behind the constricting ring. The thumbs push the glans back through the ring while the fingers draw the foreskin forward over it. It is very like working a tight ring off a swollen finger: patient, steady pressure rather than force. Lubricating gel helps.

When the ring clears the glans, relief is usually immediate. The clinician will check that the foreskin is fully forward and that color and sensation are returning, then advise on aftercare. The whole process, from cold pack to finish, often takes well under half an hour in a straightforward case, though the exact time depends on how much swelling has built up.

Paraphimosis reduction techniques compared

Clinicians choose among several approaches depending on how long the foreskin has been trapped, how swollen the tissue is, and what has already been tried. The table summarizes the options described in the NIH StatPearls review and MedlinePlus, roughly in the order they are usually attempted.

Technique	What it involves	Typical setting	Notes
Cold and compression	Cold pack, then firm wrapping of glans and foreskin to squeeze out fluid	Emergency department, urgent care, ward	Almost always the first step; minutes rather than hours
Manual reduction	Thumbs push glans back through the ring while fingers pull foreskin forward	Same	Usually done after cold or compression; local anesthetic often used
Osmotic methods	Granulated sugar or sugar-soaked gauze draws fluid out of swollen tissue	Emergency department	Slower; useful when swelling is marked
Needle puncture technique	Several small punctures in the swollen foreskin let fluid drain before manual reduction	Emergency department or urology	Used when compression alone does not shrink the tissue enough
Dorsal slit	A small cut through the constricting band along the top of the foreskin to release it	Urology, minor procedure room or theater	Reserved for failed non-surgical attempts; often followed later by circumcision
Emergency circumcision	Surgical removal of the foreskin	Operating theater	Uncommon as first-line; considered when tissue is compromised or other methods fail

No single method is right for everyone. A case caught early may need nothing beyond a cold pack and skilled hands. A case that has been swelling for most of a day may move quickly down the table. The treating clinician weighs the color and feel of the tissue, your pain, and how each attempt goes, and the decision about escalating rests with that team.

When manual reduction fails: dorsal slit and circumcision explained

Most paraphimosis is reduced without a blade. When it is not, the next steps are surgical but small, and understanding them takes away much of the fear.

A dorsal slit is a single cut made through the tight constricting band on the upper surface of the foreskin, under local anesthetic or brief general anesthesia. Releasing the band instantly relieves the constriction; blood and lymph flow return and the foreskin can be brought forward. The NIH StatPearls review describes it as the standard rescue procedure when non-surgical reduction has failed. It leaves the foreskin intact but with a cut edge, which is why many surgeons recommend a formal circumcision later, once the swelling has fully settled, to tidy the tissue and prevent a repeat episode.

Circumcision is the surgical removal of the foreskin. In the emergency setting it is uncommon as a first move but may be chosen when a dorsal slit alone is not enough, when the tissue appears compromised, or when the person has had previous episodes and wants a definitive answer. MedlinePlus notes that circumcision may be recommended to prevent paraphimosis from recurring. It is a more involved procedure than a dorsal slit, usually done in an operating theater, with healing over several weeks.

Risks are those of any minor genital surgery: bleeding, infection, pain, and scarring. The alternatives are fewer than people hope. Once the tissue is too swollen or too compromised for manual methods, leaving the constriction in place is not a safe option. Your surgeon will explain why one approach is being suggested over another, and you are entitled to ask what happens if you choose to wait for a planned procedure rather than an emergency one, where that is clinically reasonable.

Who is usually offered which treatment, and who is asked to wait

Nearly everyone with paraphimosis is offered the same first step: non-surgical reduction, as soon as possible, with pain relief appropriate to their age and distress. The differences come in what happens next.

People whose foreskin has been trapped for a short time, with modest swelling and a healthy pink glans, are the group most likely to be treated and sent home the same day with aftercare advice and a follow-up appointment. Those with a long-standing constriction, dusky or discolored tissue, or a foreskin that repeatedly slips back behind the glans after reduction are more likely to see a urologist during the same visit and to be offered a dorsal slit or circumcision. Anyone with signs of tissue compromise is treated as top priority and is not asked to wait for anything.

Who is asked to wait? Two groups, and in a specific sense. First, people whose paraphimosis has been successfully reduced and whose foreskin is now merely swollen and sore are usually asked to wait for the inflammation to settle before any planned circumcision is scheduled. Operating on swollen, bruised tissue is harder and heals less predictably. Second, people with a tight foreskin that has not become trapped, in other words phimosis, are asked to wait in a different way: this is a routine referral, not an emergency, and the NHS notes that phimosis in children often resolves as the boy grows.

Special attention goes to people with urinary catheters, who may develop paraphimosis when the foreskin is left retracted after insertion, and to those with diabetes or poor circulation, in whom tissue tolerates constriction less well. Both groups tend to be watched more closely. As always, the treatment path is set by the team examining you, based on what they see and how the first attempt goes.

Can I treat paraphimosis at home?

This is the most searched question about paraphimosis and the one with the most nuance. The direct answer: you can try one gentle step while arranging care, but you should not treat the episode as a home project.

If the foreskin has just become stuck and the swelling is minimal, a gentle attempt to slide it forward, ideally after a few minutes of a cold compress wrapped in cloth, is reasonable. Lubricating gel or a bland moisturizer can help. Use the same principle clinicians use: squeeze the glans gently to reduce its size while easing the foreskin forward. If it comes forward and stays, and the pain eases within minutes, you have averted the problem and can arrange a routine appointment to discuss why it happened.

Where home treatment goes wrong is persistence. Repeated forceful attempts bruise the tissue, worsen the swelling, and make the professional reduction harder. If the foreskin does not come forward after one or two gentle tries, stop. MedlinePlus states that if the foreskin cannot be returned to its normal position, medical help is needed right away. Do not apply ice directly to the skin, do not wrap the penis in tight bands for long periods without supervision, and do not use household remedies you have read about online; the osmotic sugar method works in a controlled setting with follow-up reduction, not as a stand-alone fix on a kitchen table.

Never try home reduction on a child beyond a single gentle attempt. Children’s tissue is delicate, fear makes the situation worse, and pediatric teams have techniques and comfort measures that parents do not.

Home care has a large role afterward. It is the wrong tool for the acute event.

Paraphimosis aftercare instructions: what the next days and weeks look like

Once the foreskin is back in place, the emergency is over but the tissue remembers. Expect the glans and foreskin to stay swollen, bruised and tender for several days. The NIH StatPearls review notes that residual edema is common after reduction and settles as lymph drainage recovers. Discomfort is usually worst in the first day or two and fades steadily.

Standard aftercare advice, echoed by MedlinePlus, is straightforward. Keep the area clean with warm water and avoid harsh soaps. Do not retract the foreskin for cleaning until the swelling has gone and a clinician has said it is safe; when you do, always pull it forward again immediately. Loose underwear reduces friction. Over-the-counter pain relief may be suggested by the treating team; follow their guidance rather than improvising, and never change any regular medicine without speaking to whoever prescribed it.

Sexual activity and masturbation are usually best avoided until the tissue is comfortable and the foreskin moves freely, typically a matter of days to a couple of weeks depending on how much swelling there was. If a dorsal slit was performed, there will be a small wound; keep it clean and dry as instructed and watch for bleeding or discharge. Circumcision has a longer recovery, generally several weeks before full activity, and your surgeon will give specific instructions.

Follow-up matters more than people expect. Paraphimosis often points to an underlying tight foreskin, and the visit to urology or your primary clinician is where recurrence is discussed. Options range from simple technique changes, such as always replacing the foreskin, to steroid creams for phimosis, which reduce inflammation and increase skin elasticity over weeks, to planned circumcision. Which is appropriate depends on your anatomy, history and preferences, and the decision sits with you and your care team.

What people often get wrong about paraphimosis

Myths about paraphimosis persist partly because it is embarrassing to ask about and partly because it is rare enough that most people never encounter it. The NIH StatPearls review puts the figure at roughly 1% of uncircumcised males older than 16, so friends and family rarely have first-hand advice.

The first mistake is believing it will resolve by itself. It does not, because the swelling maintains the trap. Every hour of waiting adds fluid, not relief.

The second is confusing it with phimosis and assuming it is a long-term nuisance to be mentioned at the next checkup. Phimosis can wait. Paraphimosis cannot.

The third is the belief that it is caused by poor hygiene or something shameful. It is caused by a foreskin being retracted and not replaced, most often during ordinary washing, sex, or a medical procedure. MedlinePlus lists catheterization and physical examination among common triggers; a significant share of cases begin in hospitals, not bedrooms.

The fourth is that treatment always means circumcision. Most cases are reduced by hand. Surgery is the fallback, and even then a dorsal slit is often the first surgical step.

The fifth is that ice on bare skin or tight home bandaging is harmless. Both can damage already compromised tissue. Cold should be wrapped, and compression should be supervised.

The sixth, and perhaps most consequential, is that a foreskin that has slipped back behind the glans a second time after reduction is nothing to worry about. Recurrence during the same episode is a signal that the ring is still too tight for the swelling and needs another look.

Finally, some people assume that because they have had a foreskin for decades without trouble, it cannot happen to them. Age does not protect against it; a catheter, a new partner, or simply forgetting once is enough.

Questions to ask your care team

The emergency room moves fast, and by the time you think of a question the clinician may be with the next patient. Having a few ready helps you leave with a plan rather than just a reduced foreskin. These are the ones patients most often wish they had asked.

• Was the foreskin fully reduced, and how will I know if it slips back behind the glans again?
• What signs over the next 48 hours should bring me straight back?
• How long should I expect the swelling and bruising to last, and what is normal versus concerning?
• Should I avoid retracting the foreskin for now, and when is it safe to start again?
• Do I have a tight foreskin that made this likely, and does that need treating?
• What are my options for preventing another episode, and what are the pros and cons of each?
• If a dorsal slit was done, what does the wound care involve, and will a circumcision be recommended later?
• If I have a catheter, what should I or my caregivers check each day?
• Who do I contact for follow-up, and how soon should that appointment be?
• Is there anything about my other medical conditions, such as diabetes, that changes the advice?

Write the answers down or ask for them in the discharge paperwork. If you were sedated, have someone with you who can hear the instructions, because memory after sedation is unreliable.

None of these questions second-guess the team. Clinicians generally welcome them, because a patient who understands what to watch for is far less likely to return with a complication that could have been caught early. And if something about the plan does not make sense to you, say so before you leave; it is much easier to clarify in the room than from home.

When to call your doctor: red-flag signs during and after paraphimosis

Seek emergency care immediately, without attempting further home treatment, if the foreskin is stuck behind the glans and any of the following applies: the glans is turning blue, purple, gray or black; the pain is severe or rapidly worsening; you cannot pass urine or the stream is only a dribble; the swelling is spreading down the shaft; the skin feels cold or numb; or the foreskin has been trapped for several hours. These signs suggest that circulation is under threat, and MedlinePlus and the NHS both advise urgent help in this situation.

After a successful reduction, call your doctor or return to the emergency department if the foreskin slips back behind the glans and will not come forward, if swelling increases rather than decreases after the first day, if you develop fever or chills, if there is pus or a foul smell, if bleeding from a dorsal slit or circumcision wound soaks through a dressing, or if the glans loses sensation or changes color. Increasing rather than easing pain in the days after treatment also deserves a call.

For people with catheters, or for caregivers of someone who cannot report symptoms, check daily that the foreskin sits forward over the glans and that there is no swelling behind it. If it has retracted, gently bring it forward; if it will not move, seek help the same day.

Children need lower thresholds. Any stuck foreskin in a child, any discoloration, or a child who is inconsolable or refusing to urinate should be seen urgently.

Where the situation is not an emergency, a routine appointment is still worthwhile if you notice a foreskin that is getting harder to retract, recurrent tightness or ballooning during urination, or repeated small episodes that you managed to fix yourself. Those are the early conversations that prevent the late-night ones. Every decision about treatment, follow-up and prevention belongs with the team who examines you.

Frequently asked questions

Should I go to the ER for paraphimosis?

Yes, if the foreskin is stuck behind the glans and will not come forward after one gentle attempt. An emergency department or urgent walk-in clinic that can see you within hours is appropriate. Go straight to the ER if the glans is changing color, pain is severe, you cannot urinate, or it has been trapped for several hours.

Can I treat paraphimosis at home?

Only as a single gentle attempt while arranging care. A cloth-wrapped cold compress for a few minutes, lubricant, and light pressure on the glans while easing the foreskin forward may work if caught very early. If it does not move after one or two tries, stop and seek medical help; repeated force worsens swelling and makes professional reduction harder.

What is mild paraphimosis?

Mild paraphimosis usually means an early case: the foreskin is stuck, there is some swelling and discomfort, but the glans is still pink and urine passes normally. It responds best to simple reduction methods, but it is still urgent, because the swelling progresses and a mild case is simply a severe one with less time elapsed.

What are the aftercare instructions for paraphimosis?

Expect swelling and bruising for several days. Keep the area clean with warm water, wear loose underwear, avoid retracting the foreskin until a clinician says it is safe, and always pull it forward afterward. Avoid sexual activity until comfortable. Attend follow-up to discuss why it happened and how to prevent recurrence, and report any color change, fever or return of the trapped foreskin.

How is paraphimosis reduction done?

Clinicians first shrink the swelling with a cold pack and firm compression, sometimes with an osmotic dressing or tiny punctures to drain fluid. Then, usually under local anesthetic, they push the glans back through the tight ring with both thumbs while drawing the foreskin forward with their fingers. If that fails, a small cut called a dorsal slit releases the band.

What is the difference between paraphimosis vs phimosis?

Phimosis is a foreskin too tight to pull back over the glans; it is common in young boys, usually painless, and often resolves with growth or is managed over weeks. Paraphimosis is a foreskin that has been pulled back and cannot return, trapping the glans; it is painful, progressive and needs same-day treatment because it can cut off blood flow.

Does paraphimosis always need circumcision?

No. Most cases are reduced by hand without any surgery. When manual methods fail, a dorsal slit, a single small cut through the constricting band, is usually the first surgical step. Circumcision may be recommended later to prevent recurrence, particularly if a tight foreskin caused the episode, but that is a planned decision made with your urologist once swelling has settled.

How long can paraphimosis go untreated?

There is no safe waiting period. The NIH StatPearls review describes the condition as progressive: venous congestion builds over hours, and prolonged constriction can eventually threaten arterial supply and tissue viability. Serious harm is uncommon because most people seek help in time, but the practical rule is to be seen the same day, ideally within a few hours.

Can a catheter cause paraphimosis?

Yes. Urinary catheter insertion requires retracting the foreskin, and if it is not pulled forward afterward it can become trapped as the glans swells. MedlinePlus and the NIH review both list medical procedures among common causes. Anyone with a catheter, or their caregivers, should check daily that the foreskin sits forward and report a stuck foreskin promptly.

Will paraphimosis happen again?

It can, especially if the underlying foreskin is tight. Recurrence risk depends on anatomy and on habits such as always replacing the foreskin after washing or sex. Your follow-up appointment is the place to discuss options, which range from technique changes to steroid creams that increase skin elasticity over weeks to planned circumcision. The choice rests with you and your care team.

References

• Paraphimosis – MedlinePlus Medical Encyclopedia
• Paraphimosis – StatPearls, NCBI Bookshelf (NIH)
• Tight foreskin (phimosis and paraphimosis) – NHS
• Circumcision – MedlinePlus Medical Encyclopedia

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.