You scoop the box at night, and by morning there’s no new clump, just a cat pacing and visiting the litter again and again. A healthy adult cat typically urinates 1–3 times in 24 hours, depending on diet and hydration. When that output drops to zero or your cat is straining without producing, it’s not just inconvenient—it can be life-threatening. Urinary obstruction can lead to dangerous potassium buildup, heart rhythm problems, and even bladder rupture in as little as 24–72 hours. This topic matters because timing is everything: waiting “to see” can turn a fixable problem into an emergency. I’ll walk you through how to tell if you should call the on-call vet, what signs mean “go now,” what to check at home while you’re lining up care, and practical details that help a busy emergency team treat your cat faster. This is informed by real cases and the small things that make a big difference at 2 a.m., when you need clarity more than anything.
Quick Answer
Yes—if your cat hasn’t urinated for 12 hours and is straining, crying, or producing only drops, call the on-call vet immediately. For male cats, inability to pass urine for even a few hours is an emergency. If your cat is lethargic, vomiting, has a firm painful belly, or you see blood, go to emergency care now.
Why This Matters
Urinary obstruction is a true emergency, especially in male cats. When urine can’t exit, waste products and potassium build up quickly. Dangerous hyperkalemia (high potassium) can cause bradycardia and life-threatening arrhythmias; without intervention, obstructed cats can decline rapidly within 24–72 hours. Kidney values (BUN/creatinine) rise, and a severely overdistended bladder may rupture.
Real-world example: your neutered male cat makes ten trips to the box, strains, vocalizes, and only a few drops appear. That pattern isn’t constipation—it’s most often a urethral blockage from crystals, mucus, or spasm. Another scenario: a typically tidy cat suddenly pees in the tub, then nothing for the rest of the day, starts vomiting, and hides; those changes indicate pain and systemic impact, not acting out.
Timely action protects your cat and your wallet. Early treatment may be outpatient for a non-obstructive irritation. Waiting can mean hospitalization with a urinary catheter for 24–72 hours, repeated bloodwork, and intensive monitoring. Fast communication with an on-call vet increases the odds of a smooth recovery and reduces complications like recurrent blockages.
Step-by-Step Guide
Step 1: Confirm it’s truly no urine, not just missed output
Check the litter box closely. Clumping litter forms discrete clumps; if none appear after 12 hours, search common “accident” spots: bathtub, tile, sink, laundry room. Place a sheet of plastic wrap over part of the litter to detect wet spots. If your cat uses non-clumping litter, you should still see damp, darker areas. You might find should i call an on-call vet for a cat not urinating kit helpful.
- Note the last time you saw a normal pee clump.
- Count litter box visits in the past 2–4 hours and whether any urine was produced.
- Look for pee outside the box—small dribbles still signal trouble.
Step 2: Check for emergency signs that mean call now
Watch for repeated straining without output, vocalizing, licking the genitals, blood-tinged urine, vomiting, lethargy, or collapse. Gently feel the lower belly: a firm, round “balloon” indicates a distended bladder. Do not squeeze.
- Male cats: obstruction is common and rapidly dangerous—act immediately.
- Heart rate: a very slow rate (under ~140 bpm) plus weakness can suggest high potassium—go now.
- Pain signs: tense posture, hiding, or snapping when the belly is touched.
Step 3: Call the on-call vet and share concise, high-impact details
Give the timeline (hours since last normal urination), sex and age, current symptoms, and any prior urinary issues. Mention water intake, appetite, vomiting, and medications or supplements. If you felt a firm bladder, say so; it helps triage.
- Have your cat’s weight, recent lab results (if any), and known conditions ready (CKD, diabetes, FLUTD).
- Ask whether to come immediately or monitor for a short window based on signs.
- Follow instructions exactly; do not give diuretics or human pain pills.
Step 4: Prepare and transport safely
Use a sturdy carrier. Line with an absorbent towel; avoid pressing on the belly when loading. Keep the environment calm and warm. Bring a photo of your litter box clumps (or lack thereof), plus meds and prior records. If vomiting or weak, cover the carrier partially to reduce stress. You might find should i call an on-call vet for a cat not urinating tool helpful.
- Do not try “bladder massages” or home catheterization—these can rupture the bladder or urethra.
- No forced fluids by syringe unless directed—aspiration risk is real.
Step 5: Comfort measures if the vet advises brief monitoring
If your vet feels obstruction is unlikely (e.g., female cat with mild signs and some urine present), they may advise short monitoring. Offer fresh water stations, a quiet room, and a clean litter box. Reduce stress: separate from other pets, dim lights, and avoid loud noises.
- Provide a wide, low-sided box to encourage easy access.
- Observe every 30–60 minutes. Any worsening or continued no-urine status—go in.
Step 6: Prevent future episodes after treatment
Discuss diet (often switching to canned, urinary-formula foods that promote dilute urine), hydration strategies (fountains, multiple bowls), and stress management (routine, play, safe spaces). Many cats with FLUTD benefit from environmental enrichment and maintaining a healthy weight. You might find should i call an on-call vet for a cat not urinating equipment helpful.
- Target at least 3–4 ounces of wet food daily if your vet agrees.
- Keep 1 litter box per cat plus one extra, scooped twice daily.
- Follow recheck schedules; recurrence rates after obstruction can be 15–40% within months, so proactive care matters.
Expert Insights
In practice, the most dangerous misconception is confusing constipation with urinary obstruction. Straining in the box looks similar, but a constipated cat often passes small hard stools; an obstructed cat produces little to no urine, visits frequently, and may cry. Another common error is waiting overnight for a male cat that’s clearly straining—many obstructed cats decompensate within 24–48 hours, and some much faster.
Professionals triage fast: signal words like “male, repeated straining, no urine in 12 hours, firm bladder, vomiting” move a case straight to emergency. Treatment for obstruction typically includes sedation, urethral catheterization, IV fluids, pain control, and monitoring electrolytes. Expect 24–72 hours of hospitalization. When potassium is high, we watch the ECG and correct electrolytes before and after unblocking.
Less obvious tip: note heart rate at home if you can feel a pulse (inside thigh). A slow rate in a distressed cat raises concern for hyperkalemia. Also, take photos of the litter box and any dribbles—those images help confirm trends quickly. Long-term, urinary diets that encourage dilute urine, more water sources, routine play, and minimizing stress (guest visits, loud events, sudden changes) reduce recurrence. And yes, overweight, sedentary, neutered males are disproportionately affected—addressing weight and activity is part of the prevention plan.
Quick Checklist
- Log the last time you saw a normal urine clump and current number of litter box visits.
- Check for straining with little to no urine, vocalizing, or blood—treat as urgent.
- Gently feel the lower belly; a firm, round bladder means call the on-call vet now.
- Observe heart rate if possible; a very slow rate with weakness is an emergency.
- Remove stressors and provide a clean, easy-access litter box while you call the vet.
- Prepare the carrier with a towel; avoid pressing on the abdomen during loading.
- Bring medication lists, prior lab results, and photos of litter box findings.
- Switch to wet food and add water stations after recovery to reduce future risk.
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Frequently Asked Questions
How long is too long for a cat not to urinate?
If your cat hasn’t urinated in 12 hours and is straining or visiting the box repeatedly, call the on-call vet. For male cats, inability to pass urine for even a few hours plus signs like pain or vomiting is an emergency. A relaxed cat with normal behavior might go less often, but zero output with effort needs professional input.
My cat is peeing tiny drops and crying—does that mean obstruction?
Tiny, painful dribbles often point to urethral obstruction or severe irritation, not simple behavioral marking. Repeated straining, blood-tinged urine, and a firm belly are red flags. Call your vet immediately; early intervention can prevent worsening electrolyte changes and reduce hospitalization time.
Can dehydration alone cause my cat to stop urinating?
Severe dehydration can reduce urine production, but most cats will still pass some urine unless there’s another problem. The combination of straining, pain, and little to no output suggests obstruction or significant urinary tract disease. Offer water and call the on-call vet to differentiate and avoid delays.
Is it safe to wait until morning if my cat isn’t peeing?
If there’s active straining, vocalizing, lethargy, vomiting, or a hard bladder, do not wait—go now. If your cat is comfortable, has peed at least a small normal amount, and is otherwise acting normal, your vet may advise close monitoring for a short window. Err on the side of calling; obstruction escalates fast.
What does emergency treatment involve, and what might it cost?
Obstruction treatment typically includes sedation, catheter placement, IV fluids, pain relief, and electrolyte monitoring for 24–72 hours. Costs vary widely by region; expect roughly $800–$2,500 for initial stabilization and hospitalization. In recurrent or severe cases, surgery (perineal urethrostomy) can range $2,000–$4,000 or more.
Could this be constipation instead of a urinary problem?
Constipation leads to hard, dry stools and straining with feces, not urine. Many owners see the effort and assume constipation when the cat is actually obstructed. If you’re unsure, gently feel the belly; a tense, round bladder and repeated trips with no pee point to the urinary tract. Call the on-call vet to confirm.
Why do male cats get urinary blockages more often?
Male cats have a longer, narrower urethra that’s prone to clogging with crystals, mucus, and urethral spasm—part of Feline Lower Urinary Tract Disease (FLUTD). Stress, low water intake, obesity, and diets that concentrate urine all contribute. Prevention focuses on hydration, routine, weight control, and appropriate diets.
Conclusion
Zero urine with effort is a clock you don’t want to ignore. If your cat hasn’t peed in 12 hours and is straining, painful, or producing only drops—especially if male—call the on-call vet and be ready to go in. While you wait, keep the environment calm, avoid pressing on the belly, and note key details like timeline and symptoms. After treatment, lean into prevention: more water, wet food, clean litter boxes, and predictable routines. Trust your instincts—quick action saves lives and often spares your cat a harder recovery.
Related: For comprehensive information about Ask A Veterinarian , visit our main guide.