Steroid pills like prednisone often do make people pee more and feel thirstier than usual.1Memorial Sloan Kettering Cancer Center. Steroid-Induced Hyperglycemia and Cancer Care2eviQ. Acute short term effects from corticosteroids The extra urine usually has one of two quite different sources: a normal shift in how the body handles water, or a rise in blood sugar that deserves a check. The steroids bodybuilders use are a separate drug family, and their effect on urination works almost the opposite way.
Which Steroids Cause More Peeing
Most people asking this question are taking a corticosteroid, which is a different family from muscle-building steroids. Corticosteroids are anti-inflammatory medicines such as prednisone, prednisolone, dexamethasone and hydrocortisone. They are used for asthma, arthritis, allergies, skin conditions and cancer care. They copy cortisol, a hormone your adrenal glands make, which helps regulate blood sugar and how the body handles water and salt. Taking extra cortisol-like medicine can therefore change how much urine you make.
People start corticosteroids in several situations. A short burst of prednisone for an asthma flare or bad poison ivy often lasts five to fourteen days. Dexamethasone is often given around chemotherapy to prevent nausea and swelling. Longer courses are used for conditions such as rheumatoid arthritis or lupus. To check which steroid you are on, read the pharmacy label. Names ending in -sone or -olone are usually corticosteroids, and dexamethasone and hydrocortisone count too despite the different ending. If you are unsure whether a medicine is a steroid, ask the pharmacist.
How the steroid reaches you matters. Pills and injections spread the drug through the whole body, while inhalers and nasal sprays keep most of it in the airways. In dogs with cough, those given prednisone tablets were noticeably thirstier and urinated more often than dogs given an inhaled steroid, from the second week onward.3PubMed Central. Comparative Study of Inhaled Fluticasone Versus Oral Prednisone in 30 Dogs with Cough and Tracheal Collapse So if you use only an inhaler, increased peeing is less likely to be from the steroid.
An inhaler does not rule the steroid out completely, though: people on high-dose inhalers, or using an inhaler along with pills, can still have some whole-body effect. Creams on small areas of skin rarely reach enough of the body to change urination, but strong creams used over large areas or for a long time can be absorbed enough to matter.
How Steroids Turn Down Your Water-Holding Hormone
Normally, when your blood becomes more concentrated, your brain releases a water-holding hormone that tells the kidneys to hold on to water. After a dose of prednisolone, this hormone stayed very low even when the blood became more concentrated.4PubMed. Effect of exogenous glucocorticoid on osmotically stimulated antidiuretic hormone secretion and on water reabsorption in man Cortisol-like drugs appear to act on the brain’s control of the hormone’s release rather than blocking it at the kidney.5Journal of Clinical Investigation. Adrenal steroid inhibition of vasopressin release from the neurohypophysis of normal subjects and patients with Addison’s disease The kidneys get a weaker “save water” message and let more water go as urine.
When the signal is weak, more of the filtered water stays in the urine, so it comes out larger in volume and paler. Pale, clear urine fits this water effect, though high blood sugar can also cause large amounts of pale urine. The brain’s thirst response usually keeps up, so people often feel thirstier too as the body tries to replace what it loses.
The kidneys also filter more. Two weeks of high-dose prednisone raised how much blood the kidneys filter, from about 93 to 102 units.6PubMed. Effect of prednisone on renal function in man In dogs, a week of high prednisolone doses also raised kidney filtering.7PubMed. Short course of immune-suppressive doses of prednisolone, evaluated through a prospective double-masked placebo-controlled clinical trial in healthy Beagles, is associated with sustained modifications in renal, hydration, and electrolytic status More filtering means more fluid moves through the kidneys each day.
This has a quirk on kidney blood tests. Creatinine can rise slightly on prednisone even when filtering improves, because steroids can increase creatinine production too. If you see a small change, ask your doctor to read it in light of the steroid.
Dose doesn’t work the way people expect. In people with heart failure, low-dose prednisone clearly increased urine output, while medium and high doses had a less obvious effect on urine volume.8PubMed. Effect of Corticosteroid on Renal Water and Sodium Excretion in Symptomatic Heart Failure: Prednisone for Renal Function Improvement Evaluation Study Higher doses made the kidneys release more salt.9PubMed. Effect of Corticosteroid on Renal Water and Sodium Excretion in Symptomatic Heart Failure: Prednisone for Renal Function Improvement Evaluation Study A bigger dose does not reliably mean more trips to the bathroom.
This water effect is usually harmless. It is the body adjusting to a hormone signal, not kidney damage.
When Extra Peeing Means High Blood Sugar
Corticosteroids make the liver release more sugar and make the body less responsive to insulin. High blood sugar caused by the medicine is a known short-term side effect.10eviQ. Acute short term effects from corticosteroids When blood sugar is high enough, sugar spills into the urine and pulls water with it.11eviQ. Acute short term effects from corticosteroids The signs are feeling very thirsty and needing to pee often.12Memorial Sloan Kettering Cancer Center. Steroid-Induced Hyperglycemia and Cancer Care
The lost water leaves you thirsty, so you drink more and pee more, a cycle that can continue until blood sugar comes back down. Signs that can point to sugar rather than the water effect include intense thirst you cannot satisfy, blurry vision, unusual tiredness or dry mouth, peeing large amounts many times day and night, and unexplained weight loss on a longer course.
People with diabetes or prediabetes usually see the largest rises on steroids. Higher doses and longer courses raise the chance of high blood sugar too. Blood sugar often peaks in the afternoon and evening after a morning dose.
A fingerstick glucose meter or a lab blood test can tell the two causes apart. Many pharmacies offer quick glucose checks. A fasting reading of 100 to 125 mg/dL is in the prediabetes range, and 126 or more suggests diabetes. People with diabetes should check more often while on steroids and ask about adjusting their medicines.
A normal reading while you are thirsty and peeing a lot points away from high blood sugar and toward the water effect, though a single reading can miss a later spike. Because rises often come in the afternoon and evening, a check a few hours after the morning dose is more revealing than a fasting one alone. If you can, check at a couple of different times of day and write the numbers down so your doctor can see the pattern.
Night-Time Peeing and Sleep on Steroids
Corticosteroids commonly cause insomnia, especially when taken later in the day. A steroid taken late is still active at bedtime, which makes it harder to fall asleep and easier to wake. Waking more often makes you notice a full bladder you might otherwise sleep through. An evening rise in blood sugar can add to night-time peeing too, so persistent waking with thirst is worth a glucose check.
Steroids can also cause fluid to collect in the legs during the day. That fluid returns to the blood and becomes urine when you lie down. Putting your feet up in the evening lets it move back earlier, and peeing right before lying down helps. Compression socks can help if your doctor agrees.
Take a once-daily steroid in the morning unless told otherwise. By night, much of the stimulation has worn off, so the effect on sleep is usually smaller. Twice-daily doses may worsen sleep, so ask whether the whole dose can be taken in the morning. Never change timing on a long course without advice.
Drink most fluids earlier in the day and cut back two to three hours before bed. Limit caffeine and alcohol in the evening, since both increase urine. Don’t cut fluids overall, though: steroids can leave you thirsty, and dehydration brings its own problems.
How Long the Extra Peeing Lasts
The kidneys can adjust to steroid hormones, so their early effect on salt and water fades with continued use.13Nephron. Kidney and Adrenocortical Hormones With a salt-holding steroid hormone, weight rose by 2 to 3 kg then stopped, and salt loss suddenly increased despite continued dosing.14Journal of Clinical Investigation. RESPONSE OF NORMAL SUBJECTS TO LARGE AMOUNTS OF ALDOSTERONE
The first few days often bring the strongest thirst and bathroom trips, as the body meets the new hormone signal. Many people find things settle somewhat after the first week or so even on the same dose. If the opposite happens and you are getting thirstier and peeing more each day, that pattern points more toward high blood sugar than a settling water effect.
For short courses, urination and blood sugar usually return to normal within days of the last dose. Prednisone is cleared from the body within about a day, and once it is gone, the water-holding hormone signal and kidney filtering return to their usual pattern. Blood sugar often falls back in step. Longer courses are tapered slowly, so changes fade gradually.
Peeing that continues weeks after stopping deserves a check for another cause. A urinary tract infection causes burning and urgency, not just volume. Diabetes may have existed before and been unmasked by the steroid. Other medicines such as water pills can be responsible, and so can high calcium in the blood, which stops the kidneys concentrating urine.
When to Call Your Doctor
- Extreme thirst with large amounts of urine
- Glucose readings above 250 mg/dL, or above the target your doctor gave you
- Dizziness, confusion, or a fast heartbeat, which can signal dehydration
- Pain, burning or blood when peeing
- Sudden weight gain or swelling that keeps growing
Have ready the drug name, dose and start date, how often you pee day and night, any glucose readings, and your other symptoms and medicines.
Don’t stop the steroid on your own in the meantime. After weeks of use, the adrenal glands slow their own cortisol making, and stopping suddenly can cause weakness, low blood pressure and vomiting. Your doctor can lower the dose safely.
Anabolic Steroids and Urination
In one reported athlete using anabolic steroids, the prostate grew and urine flow weakened.15PubMed. Steroid abuse in athletes, prostatic enlargement and bladder outflow obstruction–is there a relationship? He also woke more often at night to pee.16PubMed. Steroid abuse in athletes, prostatic enlargement and bladder outflow obstruction–is there a relationship? Frequent but weak peeing on anabolic steroids points to a blocked outflow rather than extra urine.
Anabolic steroids are testosterone-like, and the prostate grows in response to male hormones and their by-products. A larger prostate squeezes the tube that carries urine out, which is why the stream weakens. The bladder cannot empty fully, so it fills again quickly. That means frequent small trips, including at night, even though the total amount of urine may be ordinary. Men who already have some prostate enlargement are likely to notice the change first.
Anabolic steroids and high-dose vitamin supplements have been linked to kidney injury.17PubMed. Kidney disease associated with androgenic-anabolic steroids and vitamin supplements abuse: Be aware! Harms include direct kidney damage, overworked filtering and high calcium.18PubMed. Kidney disease associated with androgenic-anabolic steroids and vitamin supplements abuse: Be aware! Excess calcium can stop the kidneys concentrating urine, causing more peeing.19Journal of Clinical Investigation. On the Impairment of Renal Concentrating Ability in Prolonged Hypercalcemia and Hypercalciuria in Man
See a doctor about a weak stream, straining or dribbling. If you use these drugs, get kidney and calcium blood tests, and be honest about your use so the results are read correctly.
Dogs on Prednisone Peeing More
Dogs on prednisolone showed lasting changes in kidney function, hydration and salt balance after only a short course.20PubMed. Short course of immune-suppressive doses of prednisolone, evaluated through a prospective double-masked placebo-controlled clinical trial in healthy Beagles, is associated with sustained modifications in renal, hydration, and electrolytic status Increased thirst and peeing are among the most common prednisone side effects owners notice. Accidents in the house are usually a side effect, not bad behaviour.
Dogs may empty their water bowl faster and ask to go out more often. Urine is often pale and plentiful, and accidents may happen overnight.
Never restrict water. A dog that drinks to match its losses is protecting itself from dehydration, so keep fresh water always available. Add extra walks, including one late in the evening and an early one in the morning. Easily washable bedding or a waterproof mat can help on nights when your dog cannot hold on. If the prednisone is for a cough, ask your vet about an inhaled option. Call the vet if your dog seems lethargic or stops eating.