Is High pH in Urine Dangerous?

Urinary pH measures the amount of acid in your urine [1]. Your doctor may recommend you measure your pH in a urine test daily to monitor some conditions. But what does it mean if you have a high pH? Should you be worried? Here’s what to know.

Is High pH in Urine Dangerous?

pH measures the amount of acid on a scale of one to 14, where seven is neutral. The higher the number on the scale, the higher the pH, and the more alkaline or basic the substance is. The lower the number, the lower the pH, and the more acidic the substance [2]. 

A high urine pH level means your urine is more alkaline than usual. It generally isn’t dangerous, but it can be a sign of an underlying illness or condition, such as kidney stones or UTIs [3].  

In some cases, high urine pH links to other biomarkers, like an enzyme known as alkaline phosphatase (ALP). Your doctor may check ALP levels to evaluate your liver and bone health [4]. 

Causes of High pH in Urine

Urine is typically slightly acidic with a normal urine pH ranging from 4.5 to 8.0, but it can vary depending on how much water you drink, your diet, and certain medications [5, 6]. 

Kidney Problems

Your kidneys balance water, minerals, and salts and filter waste from your blood, removing it from the body via urine [6]. Several conditions can lead to high urine pH, including:

• ‍Renal tubular acidosis [7]
• Kidney failure [8]
• Kidney stones [3]

For instance, renal tubular acidosis is a condition in which damage to tubules in the kidneys causes problems removing acid or leaks too much bicarbonate into the urine. The urine becomes too alkaline, leading to a high pH and calcium-based kidney stones. A high urine pH is also associated with struvite and phosphate kidney stones [7]. 

UTIs

An overgrowth of urea-producing bacteria in the urinary tract can cause infections. These bacteria use an enzyme called urease to split urea into ammonia and carbon dioxide in the urine. These compounds make the urine more alkaline, producing a high urine pH [9]. 

The release of ammonia increases the alkalinity of the urine, resulting in a higher urine pH. This alkaline environment not only promotes bacterial growth but also increases the risk of forming struvite kidney stones, which are commonly associated with infections caused by urease-producing bacteria like Proteus and Klebsiella species. Managing these infections often requires targeted antibiotics and monitoring of urine pH levels to prevent complications like stone formation and recurrent UTIs [10, 11, 12].

Medications

Some medications may elevate your urine pH. These medications are typically taken for heartburn, kidney stones or other problems, and acidic urine. Drugs include [6]:

• Sodium bicarbonate or baking soda, which neutralizes stomach acid and is used for conditions like acid reflux and certain kidney stone treatments.
• Potassium citrate, commonly prescribed to treat kidney stones by making the urine less acidic, thereby preventing the formation of stones.
• Loop or thiazide diuretics, used for managing hypertension and edema, can increase urine pH by altering the kidney’s handling of electrolytes, especially bicarbonate reabsorption.

Monitoring urine pH is often recommended for patients on these medications to prevent complications such as kidney stones or urinary tract infections, which thrive in more alkaline environments [13, 14, 15].