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Home » Metformin Urine Side Effects: Excess Urine, Color, Odor, and More.

Metformin Urine Side Effects: Excess Urine, Color, Odor, and More.

Metformin, a medication for Type 2 diabetes, is not typically linked to changes in urination such as frequency, color, or smell.

Uncontrolled diabetes and other medications are more likely culprits for these symptoms. It is a generally safe kidney medication unless you have impaired renal function.

A healthcare provider should guide Metformin cessation, especially if side effects occur.

In this article, I will delve into the possible changes in urine and its link to metformin.

Bullet summary:

Here are some fast facts about metformin urine side effects:

  • Frequent Urination: Not caused by Metformin; likely due to uncontrolled diabetes or other medications.
  • Urine Color: Metformin doesn’t typically change urine color; rare cases may cause dark urine.
  • Smelly Urine: Not directly caused by Metformin; related to diet, dehydration, or infections.
  • Bloody Urine: Not associated with Metformin; consider other underlying causes.
  • Long-Term Kidney Effects: Metformin is generally safe; a rare condition called lactic acidosis may occur.
  • Stopping Metformin: Should be done under healthcare provider guidance; this may be due to kidney impairment or serious side effects.

Metformin and frequent or excess urination?

Metformin is a well-known medication used to manage Type 2 diabetes. Metformin is not known to cause frequent or excess urination (reference).

If you are taking metformin and going to the bathroom a lot, the most likely cause is diabetes itself and not metformin. When diabetes is poorly controlled, and your blood sugar is high, you will have frequent urination and excess urine (large urine volume).

So, check for your blood sugar as a first step when urinating frequently while on metformin.

Possible causes of frequent or excess urination while on metformin.

  1. Uncontrolled Diabetes: If your blood sugar levels are not well-controlled, your body may try to get rid of excess glucose through urination.
  2. Other Medications: If you’re taking other medications alongside Metformin, they might be the cause of increased urination. Common medications include:
    1. Diuretic medications such as Hydrochlorothiazide (present in many antihypertensive medications).
    2. SGLT2 inhibitors (anti-diabetes, commonly used in combination with metformin) are known to also increase urine (polyuria) despite normal blood sugar.
    3. Lithium and antiseizure medications.
    4. Corticosteroids.
    5. Some antidepressant medications.
    6. Calcium channel blockers such as amlodipine.
  3. Underlying Health Conditions: Conditions like hypercalcemia, diabetic ketoacidosis, lactic acidosis, or kidney issues might lead to Polyuria.
  4. Lifestyle Factors: High fluid intake, consumption of diuretic substances like caffeine, or a diet high in sugar can also lead to increased urination.

I’ve written a complete in-depth article about the causes of frequent and clear urine.

So, while Metformin itself doesn’t directly cause Polyuria, the indirect effects of the medication, along with other factors, might lead to this condition. See a doctor if you are in doubt.

Treatment of polyuria:

The treatment of polyuria during metformin therapy depends on diagnosing the original causes. Common treatments according to the cause include:

  • Control of blood sugar (by adjusting the dose of metformin or adding other medications).
  • Working with your doctor to adjust or replace the medications that cause polyuria (sometimes, excess urine is a desirable effect of the medication. So your doctor may decide not to change the medication).
  • Treatment of related health conditions causing polyuria, such as hypercalcemia.
  • Limit the use of caffeine.

Does metformin change the color of urine?

The Short Answer

No, Metformin itself does not typically change the color of urine. However, it may rarely cause hemolytic anemia (leading to dark urine).

The Longer Explanation

While Metformin doesn’t directly cause a change in urine color, it’s worth noting that some underlying conditions or other medications taken alongside Metformin might lead to changes in urine color.

Rarely, metformin may cause a condition called hemolytic anemia (destruction of the blood cells) which may cause jaundice and dark urine (the color may appear shortly after urination) (reference).

Does metformin cause dark urine?

While taking Metformin, the color of your urine might change, but it’s essential to understand that these changes are typically not directly caused by the medication itself. Let’s dive into the factors that might lead to darker or lighter urine.

1. Darker Urine

Darker urine can be a sign of various factors unrelated to Metformin:

  • Dehydration: Lack of enough fluids can concentrate the urine, leading to a darker color.
  • Diet: Certain foods like asparagus, beets, and berries can darken the urine.
  • Other Medications: If you’re taking other medications alongside Metformin, they might cause the urine to darken.
  • Liver or Kidney Issues: Sometimes, darker urine might indicate a problem with the liver or kidneys, which could be an underlying condition related to diabetes.

Learn more: The causes of painless dark brown urine in women.**

2. Lighter Urine

Lighter urine is usually less concerning and can be attributed to the following:

  • Increased Fluid Intake: Drinking more water will dilute the urine, leading to a lighter color.
  • Diuretics: If you’re taking diuretics along with Metformin, they can increase urine production, leading to a lighter color.

Learn more about the causes of dark urine.

Metformin’s Role

It’s worth reiterating that Metformin doesn’t typically cause changes in urine color. However, since it’s often prescribed for type 2 diabetes, the underlying condition and associated lifestyle factors might indirectly lead to changes in urine color.

What to Do If You Notice a Change?

If you observe a persistent change in your urine color while taking Metformin, it’s not something to ignore. Reach out to your healthcare provider. They can conduct an examination and run tests to pinpoint the exact cause.

Does metformin cause smelly urine?

The short answer is no. Metformin itself doesn’t typically cause urine to have an unpleasant odor.

Metformin’s role in medicine is well-established, but its connection to smelly urine is more of a myth than a reality. The causes of smelly urine while taking Metformin are more likely related to diet, dehydration, infections, or other medications.

The causes of smelly urine while taking metformin

While Metformin isn’t directly responsible for smelly urine, several factors might lead to this condition:

  1. Dietary Choices: Foods like asparagus, fish, and certain vegetables can cause a distinct urine odor. These dietary factors are unrelated to Metformin but might coincide with its use.
  2. Dehydration: Concentrated urine due to dehydration can have a stronger smell. Since diabetes can lead to frequent urination, dehydration might lead to smelly urine.
  3. Urinary Tract Infections (UTIs): UTIs can cause foul-smelling urine. If you’re taking Metformin, it’s likely due to diabetes, and diabetes can increase the risk of UTIs.
  4. Other Medications: If you’re taking other medications alongside Metformin, they might interact in a way that leads to smelly urine.
  5. Metabolic Factors: Diabetes itself can sometimes cause changes in the smell of urine due to how the body metabolizes food and waste products.

What to do if you notice smelly urine?

If you experience persistent smelly urine while taking Metformin, don’t jump to conclusions. It’s likely unrelated to the medication. However, consulting with your healthcare provider is a wise step. They can perform tests to determine the cause and provide appropriate treatment.

Can metformin cause blood in urine?

Metformin is a medication primarily used to treat type 2 diabetes. It works by controlling blood sugar levels, but it is not typically associated with causing bloody urine.

If you are getting blood or blood clots in urine while taking metformin, it is better to consider other causes of

Possible Causes of Bloody Urine While Taking Metformin

While Metformin itself is unlikely to cause bloody urine, there might be underlying factors or conditions that could lead to this symptom:

  1. Kidney Stones or Infections: These can cause blood in the urine and might be more common in individuals with diabetes.
  2. Bladder or Urinary Tract Infections (UTIs): These infections can cause bloody urine, and people with diabetes may be at a higher risk.
  3. Other Medications: If you’re taking other medications alongside Metformin, they might have side effects that cause bloody urine.
  4. Underlying Health Conditions: Conditions like hematuria or certain types of kidney disease could lead to bloody urine.

What are the known side effects of metformin?

These are the possible side effects of the medicine. Some people might experience them, but not everyone will.

Here are the most common side effects (reference)

Common Side Effects (More than 10% of people might experience)

  • Stomach Problems:
    • Diarrhea (53% with one type of tablet, 10% with another)
    • Gas (12%)
    • Nausea and Vomiting (26% and 7%, respectively)

Less Common Side Effects (1% to 10% of people might experience)

  • Heart-Related: Discomfort in the chest, flushing, heartbeat feels strange (palpitations)
  • Skin: Sweating, problems with nails
  • Hormones & Metabolism: Low blood sugar, lack of vitamin B12 (7%)
  • Stomach: Bloating, stomach pain, weird stools, indigestion (7%), heartburn
  • Nervous System: Chills, feeling dizzy, headaches (6%)
  • Muscles & Bones: Weakness (9%), muscle pain
  • Breathing: Shortness of breath, flu symptoms, infection in the upper breathing area

Rare Side Effects (Reported after the medicine was released)

  • Skin: A skin condition called Lichen planus
  • Hormones & Metabolism: A rare condition called Lactic acidosis (less than 1%)
  • Hemolytic anemia: Destruction of the red blood cells leading to anemia and dark urine
  • Liver: Liver damage
  • Allergies: A specific allergic reaction
  • Nervous System: A brain condition called Encephalopathy

These side effects are listed based on how often they might happen and what part of the body they affect. If you have any concerns or notice any of these side effects, it’s a good idea to talk to a doctor or healthcare provider. They can help you understand what’s going on and what to do about it.

Other FAQs about Metformin Urine Side Effects:

1. Does Metformin Cause Urine Urgency?

Metformin itself is not typically associated with causing urine urgency. However, individuals with diabetes may experience increased urination due to high blood sugar levels or UTI. UTI is the most common cause of urine urgency, particularly in women with diabetes. Contact your doctor to get tested for UTI if you are experiencing urgency while taking metformin.

2. What Are the Long-Term Side Effects of Metformin on the Kidney?

Metformin is generally considered safe for the kidneys. However, in rare cases, it might cause a condition called lactic acidosis, particularly in individuals with pre-existing kidney problems. Long-term use of Metformin should be monitored by a healthcare provider to ensure that kidney function remains healthy.

3. When to Stop Metformin

Stopping Metformin should never be done without consulting a healthcare provider. Situations that might warrant stopping include:

  • Severe kidney impairment
  • Before certain medical procedures
  • If serious side effects occur

Your healthcare provider will guide you on when and how to stop Metformin safely based on your health condition and needs.

4. Can Metformin Cause Kidney Failure?

Metformin itself is not known to cause kidney failure. However, it should be used with caution in individuals with pre-existing kidney disease or impaired kidney function. Regular monitoring of kidney function is essential when taking Metformin, especially for those at higher risk.