Medications That Change the Color of Urine

Occasionally, the color of urine can vary, adopting very striking tones, such as blue or orange. We explain why.

Reviewed and approved by the doctor Elisa Martin Cano.

Written by Elisa Martin Cano

Last update: 17 February, 2023

The color of urine is an indicator of certain processes taking place in our body. Normally, urine varies between different shades of yellow, depending on how much water a person drinks or their level of dehydration.

However, certain medications cause the color of this liquid to change. This doesn’t mean that it becomes darker or lighter, but that it can acquire very bright shades, such as red, yellow, green, or even blue.

Normally, people who don’t know about this fact are afraid. Therefore, in this article, we’ll explain which medications can cause the color of urine to change.

Why might the color of urine change?

Although the tone usually varies a little, even in the same person, it’s normal for urine to be in the yellow spectrum, ranging from dark amber to almost transparent yellow. This is due to the presence of a natural pigment called urochrome.

On the other hand, there are several reasons why the color of urine can change. These have to do with hydration or dehydration, as well as infections or consumption of food and medicines.

In this order of ideas, the amount of liquid that the person has taken will affect the concentration and, therefore, the tone. The clearer the urine, the better the hydration, and vice versa.

On the other hand, what we have consumed can vary the color, causing our urine to change color. In this way, pigments as well as different ingredients in food affect what we perceive when we go to the bathroom. Very strong seasonings, such as curry, give a particular odor and appearance.

However, in addition to this, certain diseases can also have an effect. In urinary infections and when there are kidney stones, urine becomes reddish due to the presence of blood.

Medications that change the color of urine

Changes in tone also occur with some medications, as you will see below.

When urine becomes red

If urine becomes pink or reddish, it’s logical to be startled and think that something is wrong. The truth is that, on numerous occasions, the presence of blood in this liquid is what causes this.

In addition to the above with regard to infections and kidney stones, it can also be a consequence of the use of anticoagulants, such as warfarin and heparin.

Likewise, other drugs also cause this problem due to their metabolism. For example, one drug that is frequently associated with this is rifampicin. This is an antibiotic that is used to treat tuberculosis.

In addition, certain laxatives containing senna (an herbal component) change the color of the urine to red. The same happens with phenazopyridine, which is a drug that acts as an analgesic in the urinary tract, for colic in the region or urinary tract infections with pain.

But if this is not the cause, it is also worth asking whether it is something we have eaten. In this regard, among the foods that can produce this tone are beets, blackberries, and other red fruits, as well as rhubarb.

Green or blue urine

Although it seems incredible, this liquid sometimes takes on a blue-green color. First of all, it may be due to amitriptyline. This is an antidepressant that is used not only for this purpose, but is also indicated for fibromyalgia and neuropathic pain, among other conditions.

Additionally, this shade may be due to indomethacin. Indomethacin is a drug that is very commonly used in people with rheumatoid arthritis, acute gout, and other musculoskeletal disorders.

Similarly, these hue changes have been reported with propofol, which is used as part of general anesthesia and for sedation. Such medication can cause the urine to be greenish.

If this is not the case with any of these drugs, this color may also be due to a disorder known as hereditary benign hypercalcemia.

When urine is orange

Sometimes the orange and reddish colors of urine are similar. Therefore, in this category, we can also include drugs already mentioned, such as rifampicin and phenazopyridine, since some people consider that the tone acquired is more orange than red.

Another drug that can cause urine to turn orange is sulfasalazine. This is an anti-inflammatory drug common in the treatment of ulcerative colitis or Crohn’s disease.

Nitrofurantoin, an antibiotic indicated in urinary tract infections, and vitamin B supplements, have also been linked to this situation.

Brown urine

Occasionally, urine may darken to a dark yellow or even brownish color. First of all, it may be due to the use of some antibiotics.

For example, there is metronidazole, a common treatment for Trichomonas vaginitis and urethritis. Similarly, it is useful for intestinal amebiasis and Clostridium perfringens infection.

On the other hand, antimalarials (antimalarial drugs) also cause the urine to turn brown. Chloroquine and primaquine fall into this group.

If this is not the case, the next options for brown urine are certain foods (e.g., beans), as well as liver disorders and urinary tract infections.

Urine color has changed: Should I go to the doctor?

Urine color is usually yellow and varies in intensity depending on how well-hydrated the person is. However, as you’ve already seen, many medications can cause this liquid to adopt very different colors, such as red, orange, or even blue.

If you are taking a specific drug for a pathology you are suffering from, your doctor will inform you of the possible adverse effects of the drug, which may include chromatic alterations of the urine. Similarly, drug package inserts often describe the possibility.

What you should bear in mind is that, in the event of unexpected changes in the color of urine, it’s always best to consult a doctor. While it’s true that this is usually a benign side effect, it may also indicate that something is wrong with the body if it lingers.