Urine color
Definition
Normal urine color ranges from pale yellow to deep amber — the result of a pigment called urochrome and how diluted or concentrated the urine is.
Pigments and other compounds in certain foods and medications may change your urine color. Beets, berries and fava beans are among the foods most likely to affect urine color. Many over-the-counter and prescription medications give urine more-vivid tones — raspberry red, lemon yellow and orange orange.
An unusual urine color is among the most common signs of a urinary tract infection. Deep purple urine is an identifying characteristic of porphyria, a rare, inherited disorder of red blood cells.
Symptoms
Normal urine color varies, depending on how much water you drink. Fluids dilute the yellow pigments in urine, so the more you drink, the clearer your urine looks. When you drink less, the color becomes more concentrated. Severe dehydration can produce urine the color of amber.
But sometimes urine can turn colors far beyond what's normal, including red, blue, green, dark brown and cloudy white.
When to see a doctor
Seek medical attention if you have:
- Visible blood in your urine. Bloody urine is common in urinary tract infections and kidney stones. Both of these problems usually cause pain. Painless bleeding may signal more serious problems, such as cancer.
- Dark brown urine. If your urine is dark brown — particularly if you also have pale stools and yellow skin and eyes — your liver might be malfunctioning.
Causes
Discolored urine is often caused by medications, certain foods or food dyes. In some cases, though, changes in urine color may be caused by certain health problems.
Red or pink urine
Despite its alarming appearance, red urine isn't necessarily serious. Red or pink urine may be caused by:
- Blood. Factors that can cause urinary blood (hematuria) include urinary tract infections, enlarged prostate, cancerous and noncancerous tumors, kidney cysts, long-distance running, and kidney or bladder stones.
- Foods. Beets, blackberries and rhubarb can turn urine red or pink.
- Medications. Rifampin (Rifadin, Rimactane), an antibiotic often used to treat tuberculosis, can turn urine red — as can phenazopyridine (Pyridium), a drug that numbs urinary tract discomfort, and laxatives containing senna.
- Toxins. Chronic lead or mercury poisoning can cause urine to turn red.
Orange urine
Orange urine is hard to miss. Blame it on:
- Medications. Medications that can turn urine orange include rifampin; the anti-inflammatory drug sulfasalazine (Azulfidine); phenazopyridine (Pyridium), a drug that numbs urinary tract discomfort; some laxatives; and certain chemotherapy drugs.
- Medical conditions. In some cases, orange urine can indicate a problem with your liver or bile duct, especially if you also have light-colored stools. Orange urine may also be caused by dehydration, which can concentrate your urine and make it much deeper in color.
Blue or green urine
Blue or green urine can result from:
- Dyes. Some brightly colored food dyes can cause green urine. Dyes used for some tests of kidney and bladder function can turn urine blue.
- Medications. A number of medications produce blue or green urine, including amitriptyline, indomethacin (Indocin) and propofol (Diprivan).
- Medical conditions. Familial hypercalcemia, a rare inherited disorder, is sometimes called blue diaper syndrome because children with the disorder have blue urine. Green urine sometimes occurs during urinary tract infections caused by pseudomonas bacteria.
Dark brown or tea-colored urine
- Food. Eating large amounts of fava beans, rhubarb or aloe can cause dark brown urine.
- Medications. A number of drugs can darken urine, including the antimalarial drugs chloroquine and primaquine, the antibiotics metronidazole and nitrofurantoin, laxatives containing cascara or senna, and methocarbamol — a muscle relaxant.
- Medical conditions. Some liver and kidney disorders can turn urine dark brown, as can some urinary tract infections.
Cloudy or murky urine
Urinary tract infections and kidney stones can cause urine to appear cloudy or murky.
Risk factors
Eating foods that can discolor urine, such as berries, beets and rhubarb, or taking certain medications makes it more likely that you'll have harmless changes in the color of your urine. Whether you react or not depends on the amount of food or medication you take, your state of hydration, and your own body chemistry.
Factors that put you at risk of medical conditions that can affect urine color include the following:
- Age. Tumors of the bladder and kidney, which can cause blood in the urine, are more common in older people. Men older than 50 occasionally have urinary blood due to an enlarged prostate gland.
- Your sex. More than half of all women will have a urinary tract infection at some point, often with some urinary bleeding. Men are more likely to have kidney stones or bladder stones.
- Family history. A family history of kidney disease or kidney stones makes it more likely that you'll develop these problems. Both can cause blood in the urine.
- Strenuous exercise. Distance runners are most at risk, but anyone who exercises vigorously can have urinary bleeding.
Preparing for your appointment
You're likely to start by seeing your family doctor or primary care provider. In some cases, though, you might be referred immediately to a doctor who specializes in urinary tract disorders (urologist).
Here's some information to help you prepare for your appointment, and what to expect from your doctor.
What you can do
- Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in advance to prepare for common diagnostic tests.
- Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
- Make a list of your key medical information, including any other conditions for which you're being treated, and the names of any medications, vitamins or supplements you're taking.
- Consider questions to ask your doctor and write them down. Bring along notepaper and a pen to jot down information as your doctor addresses your questions.
What to expect from your doctor
Your doctor or health care provider is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on.
Questions your doctor might ask include:
- What color is your urine?
- Do you see blood or blood clots in your urine?
- When did you first notice the unusual urine color?
- Does it happen all the time or only sometimes?
- Do you also notice an unusual odor to your urine?
- Are you urinating more or less frequently than usual?
- Do you have pain while urinating?
- What other symptoms are you experiencing?
- Has your appetite changed?
- Do you seem to be more or less thirsty than usual?
- Have you had any previous urinary problems?
- Do you have any allergies?
- What medications are you taking?
Tests and diagnosis
In addition to taking a thorough medical history and performing a physical exam, your doctor will recommend certain diagnostic tests, including:
- Urinalysis. A thorough urine analysis is the most important first step. Urine tests are used to look for the presence of red blood cells, high levels of protein — which may indicate a kidney problem — and excreted minerals that can cause kidney stones. A sample of your urine is also likely to be checked for bacteria that cause infection.
- Blood tests. These may be used to measure levels of creatinine and blood urea nitrogen (BUN) — waste products that build up in your bloodstream when your kidneys are damaged and not filtering properly. Blood tests may also look for elevated levels of liver enzymes, and for conditions such as diabetes.