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Home > Key Issues > Constipation
Overview
- Many CKD cats suffer from constipation, and treating or preventing it can make a big difference to your cat's quality of life.
- It is important to keep a close eye on your cat's litter tray and to deal promptly with any signs of constipation or straining.
- Obviously the ideal is to prevent constipation from ever happening, but that is not always possible.
- Which treatments to use depends largely upon how severe your cat's problem is, and whether it is an acute problem or a chronic problem.
Feline constipation: getting crap out of a cat(2018) Webb CR
PVMA Veterinary Conference discusses constipation.
Feline Constipation is a detailed and helpful website about constipation.
International Cat Care has a helpful overview of constipation.
Mar Vista Vetdiscusses constipation and megacolon.
Survey of defecation habits in apparently healthy and chronic kidney disease cats(2022) Jones SE, Quimby JM, Summers SC, Adams SM, Caney SMA & Rudinsky AJ
Journal of Feline Medicine and Surgery 24(2) pp131-141 states "Constipation can be a significant clinical problem in cats with chronic kidney disease (CKD)...Under-recognition of subclinical constipation in CKD cats is likely."
This lack of recognition of the problem can lead to the constipation becoming acute, which in some cases results in a trip to the ER.
Retrospective evaluation of risk factors and treatment outcome predictors in cats presenting to the emergency room for constipation(2020) Benjamin SE & Drobatz KJ
Journal of Feline Medicine and Surgery 22(2) pp153-160 looked at cats presenting to the ER with severe constipation and says "cats with chronic kidney disease or previous episodes of constipation were found to be at increased risk of constipation." Increased age or obesity were also factors.
Chronic renal insufficiency and its associated disorders kitty kidneys and the kitchen sink(2007) Scherk M
The 2007 Nestlé Purina Veterinary Symposium on Companion Animal Medicine says "For the most part, constipation is a clinical sign of dehydration." This is certainly a major factor in CKD cats.
In addition to concentrating urine, a cat's body also tries to conserve water by reabsorbing it from the stool through the intestinal wall. This mechanism is very efficient, and remains so even in CKD cats, and since CKD cats are largely on the edge of dehydration most of the time, the intestine will wring every drop of water out of the stool that it can, leaving it quite dry. The lack of moisture as a lubricant makes it more difficult for the cat to have bowel movements and can lead to constipation.
Some cases of constipation are caused by
low potassium levels or by
high calcium levels. Treating these problems may resolve or improve the constipation.
Some of the medications commonly used in CKD cats, such as
phosphorus binders or
sucralfate, may also cause constipation. Some
painkillers such as
buprenorphine may also contribute to constipation.
Constipation is sometimes caused by external factors, e.g. if you put the litter tray up two flights of stairs and your elderly, arthritic cat finds it hard to get up the stairs to it, or if the tray is where your family dog can disturb the cat in the tray.
All bunged up unclogging the constipated cat(2015) M Scherk
Veterinary Medicine discusses the causes of constipation.
Survey of defecation habits in apparently healthy and chronic kidney disease cats(2022) Jones SE, Quimby JM, Summers SC, Adams SM, Caney SMA & Rudinsky AJ
Journal of Feline Medicine and Surgery24(2) pp131-141 states "Causes include dehydration, electrolyte abnormalities, gastrointestinal alterations and medications prescribed."
cognitive dysfunction.
Vomiting Before, During or Immediately After Using the Tray
Survey of defecation habits in apparently healthy and chronic kidney disease cats(2022) Jones SE, Quimby JM, Summers SC, Adams SM, Caney SMA & Rudinsky AJ
Journal of Feline Medicine and Surgery24(2) pp131-141 found that "more cats in the CKD group showed signs of vomiting, vocalising and straining around the time of defaecation."
Newman Veterinary mentions (scroll down to Constipation) that constipation may cause vomiting because "stretch receptors within the serosa in the colon (or even serosal surfaces of other abdominal viscera) respond to distension and transmit signals to the vomit center of the brain inducing the vomit reflex."
Urinating Outside the Litter Tray
Most people assume this is because of a urine-related problem (e.g. a urinary tract infection) or a behavioural problem, but it can actually be a sign of constipation. My Karma peed on the sofa so I took her to the vet for a suspected urinary tract infection, but in fact she did not have one, her problem was constipation. Once the constipation was under control, her inappropriate elimination ceased.
The University of California at San Francisco Department of Urology states "There is a close relationship between the muscles and nerves that control bladder functions and those that control bowel movements. In addition, the bladder and the colon are close together in the body. Large amounts of stool in the colon can put pressure on the bladder which can cause the bladder to not fill as much as it should, or cause the bladder to contract when the bladder is not supposed to contract. This large amount of stool can also cause the bladder to not empty well. All of these problems can lead to daytime wetting, nighttime wetting, urinary tract infections."
Diarrhoea
You see a runny poop in the litter tray so you think (reasonably enough) that your cat has diarrhoea but in fact the true problem is sometimes constipation, and the runny stool is simply what can squeeze around the solid dry stool.
Frequent Visits to the Litter Tray
This may sometimes be a sign of constipation but may also be a sign of a urinary tract infection.
It may also be a sign of a very serious problem, i.e. the inability to pass urine. I made this mistake myself with one of my cats when I saw this symptom and thought he was constipated when in fact he had a urinary tract blockage (luckily, despite my ignorance, I still got him to the vet in time to save him).
If your cat cannot pass urine, this is a medical emergency and you need to go to the vet immediately.
Fast Breathing and Fast Heart Rate
One of my cats once had an episode of fast breathing and fast heart rate. He had severe constipation, and his problems resolved once he had been given an enema. If a cat is very severely constipated, toxins can back up in the cat's system causing such problems; pain or discomfort can also cause fast breathing, and severe constipation can be extremely uncomfortable. Alternatively you might see lethargy and fainting, known as vasovagal syncope - syncope means to faint.
Medicine Net discusses this.
Obviously you do not want your cat to have such severe constipation that these problems arise!
Frequent Visits to the Litter Tray
Other possible symptoms include:
- Dry and hard stools
- Straining in the litter tray
- Lying in the litter box
- Loss of appetite
- An ungainly walk
Here is a video from Dr Margie Scherk on how to recognise constipation in your cat, courtesy of
DVM360.
Purina
Bristol stool form scalefor humans but hey, poop is poop.
Emergency Vets USA discuss the meaning of the different colours of cat poop.
acute constipation
Fluid therapy
intravenous fluids, or may give a smaller amount of fluid
subcutaneously.
Feline Constipation advises that if you are using a liquid glycerin suppository, after you have squeezed on the bulb to inject the suppository into your cat, you should keep squeezing the bulb until you have removed the tip from your cat.
Feline constipation, obstipation and megacolon: prevention, diagnosis and treatment (2001) Washabau R Presentation to the World Small Animal Veterinary Association World Congress has information about rectal suppositories and enemas.
Enema Cautions), but your vet will use one that is safe for your cat.
Enemas can be messy so are normally given at the vet's, but some members of Tanya's Support Group whose cats need enemas regularly have been taught how to give them at home.
One popular brand in the USA is Pet-Ema 6ml, which is designed especially for cats.
Medi-Vet sells Pet-Emas for US$5.39 each.
Amazon sells the Pet-Ema for US$7.78 each. These are also available from Amazon UK but are much more expensive (about £20).
Vet Depotsells Pet-Emas for US$9.58 each.
Feline constipation, obstipation and megacolon: prevention, diagnosis and treatment (2001) Washabau R Presentation to the World Small Animal Veterinary Association World Congress has information about rectal suppositories and enemas.
Constipation and obstipation in small animals (2020) Defarges A Merck Veterinary Manual states "Phosphate-containing enemas must be avoided in cats."
Constipation in catsDuddy J Angell Medical Center says "Do not use enema solutions containing sodium phosphate (Fleet) as they predispose to life-threatening electrolyte imbalances (hypernatremia, hyperphosphatemia and hypocalcemia)."
Electrolyte abnormalities induced by hypertonic phosphate enemas in two cats (1985) Jorgensen LS, Center SA, Randolph JF & Brum D Journal of the American Veterinary Medical Association 187 pp1367-8reports on two cats who suffered severe problems after such enemas, and advises against their use for cats with renal problems in particular.
Troublesome toxicoses in cats(2011) Dowers K Veterinary Medicineexplains more about this problem, including symptoms and treatment options should a cat accidentally be given such an enema.
Feline constipation, obstipation and megacolon: prevention, diagnosis and treatment(2001) Washabau R Presentation to the World Small Animal Veterinary Association World Congress explains more about this and mentions that it can be safer to do this over a period of several days.
Acute Treatments, and you can then try to maintain your cat at home. If you are ever concerned though, always contact your vet.
All bunged up unclogging the constipated cat(2015) M Scherk Veterinary Medicine discusses the various treatments available for constipation.
Chronic renal insufficiency and its associated disorders kitty kidneys and the kitchen sink(2007) Scherk M The 2007 Nestlé Purina Veterinary Symposium on Companion Animal Medicine says "primary treatment should address rehydration and the underlying cause of dehydration, rather than stool passage (e.g., with laxatives). Promotility agents, laxatives, osmotic agents, and fiber-enriched diets should be used only after the patient is rehydrated."
Please ensure there are plenty of water drinking opportunities available for your cat. Water fountains can be helpful. See Oral Fluids for more information.
Also consider feeding canned food in preference to dry foods.
Most CKD cats will eventually be receiving sub-Q fluids regularly to maintain hydration, and these may also help with constipation. However, they are not normally given solely to assist with constipation. Please seeSubcutaneous Fluids for more information about this treatment.
Holistic Treatments.
vitamin B12 in the form of methylcobalamin is a helpful preventative treatment.
Methylcobalamin is a popular choice for CKD cats too, and many people find that it seems to help with constipation.
All bunged up unclogging the constipated cat(2015) Scherk M Veterinary Medicine states "Moderately fermentable fibers such as beet pulp are preferable to a highly fermentable, high-gas-forming fiber source." See Nutritional Requirements for more information on fibre, including beet pulp.
Be careful if using additional fibre in diabetic cats, because fibre may reduce blood sugar levels.
Some vets in the USA recommend a product called Benefiber. This used to contain a type of fibre called guar gum, but it now contains wheat dextrin. I think there are better choices available for cats.
Fibre-Enriched Foods
I have heard from a couple of people that a Royal Canin product,Veterinary Diet Gastrointestinal Fiber Responseis helping with their cats' constipation. I have not been able to obtain any information on its phosphorus or protein levels as yet, but will try again. The people I have heard from do not feed this food exclusively.
One vet told me that Hill's i/d food can help some cats. The canned version contains 0.79% phosphorus and 40% protein on a dry matter analysis, which are not unreasonable levels for most CKD cats.
Canned Foods USA), and many of them seem to have reasonable levels of phosphorus, though unfortunately they tend to have rather high levels of protein.
You do not need to cook the pumpkin if you buy the canned products listed below. You should start gradually, say with half a teaspoon of pumpkin once or twice a day (it can be mixed with food), and increase as needed.
If you buy fresh pumpkin, you will need to cook it before use. The Pioneer Woman has an oven recipe, while A Pinch of Healthy has instructions for cooking it in an instant pot.
You can freeze unused pumpkin in ice cube trays and just take out what you need for each day, though freezing it can change the texture somewhat.
Pumpkin itself is low in phosphorus. According to the USDA National Nutrient Database, pumpkin cooked, boiled and drained without salt contains 0.48% phosphorus on a dry matter analysis basis. Pumpkin canned without salt contains 0.35% phosphorus on a dry matter analysis basis.
USA
In the USA canned pumpkin is usually widely available in supermarkets, though there was a shortage in the summer of 2010.
Amazon sells Farmer's Market Organic Pumpkin online, as well as pther brands, including Libby's.
Vitacost also sells Farmer's Market Organic Pumpkin.
Amazon sells Raw Paws pumpkin powder, which may be easier to give to your cat.
Pumpkin Patch Up!is a pumpkin product for cats from Weruva.
UK
Tinned pumpkin can be harder to find in the UK, but some branches of Waitrose and Sainsbury's sell American canned pumpkin with no additives in the canned vegetables aisle.
Some people have found fresh cubed pumpkin is sometimes available, e.g. from Marks and Spencer. This needs to be cooked before use.
Amazon sells the Libby's brand online in the UK.
Waitrose also sells Libby's though it is not always in stock.
Uncontrolled study assessing the impact of a psyllium-enriched extruded dry diet on faecal consistency in cats with constipation (2011) Freiche V, Houston D, Weese H, Evason M, Deswarte G, Ettinger G, Soulard Y, Biourge V, German AJ Journal of Feline Medicine and Surgery 13(12)pp903-11 found that a psyllium-enriched diet was effective at controlling chronic constipation in cats.
In the USA psyllium is commonly sold under the name of Metamucil.Drugs has some information about this. Be sure not to buy Metamucil Clear and Natural (blue container) because this does not contain psyllium.
You may prefer to buy a veterinary product such as Vetasyl fiber capsules. Drugs has some information about this product. The usual dose is ½ to 1 capsule, depending upon the size of the cat. The product can be mixed with food. I don't recommend Animal Essentials Colon Rescue because it contains liquorice, which may raise blood pressure.
In the UK, your vet may offer you a standardised pharmaceutical-grade fibre called Nutrifyba. Neals Yard Remediesalso sell psyllium husks.
If you are using loose psyllium, you only need to give a tiny amount. The maximum dose is ⅛th of a teaspoon, but you should start with an even smaller dose.
With fibre-based treatments, it is very important to ensure that the cat drinks plenty of water, otherwise the fibre can bulk up in the body and make the constipation worse. Therefore if you mix it with your cat's food, it is probably wise to add a little water too.
Be careful how you handle psyllium: Psyllium: keeping this boon for patients from becoming a bane for providers(2006) Hoffman D The Journal of Family Practice 55(9) pp770-772reports on the case of an asthmatic nurse who died after inhaling psyllium powder, and recommends spooning it rather than pouring it.
Too much fibre may prevent your cat from absorbing sufficient nutrients or calories from his/her food. In humans, some types of fibre may also bind calcium in the small intestine and lead to an increase in calcium levels in the body (hypercalcaemia). If you are only giving a small amount to prevent constipation, your cat will probably be fine, but be careful if your cat already has hypercalcaemia.
Drugs states that "Psyllium may interact with other medications if given at the same time. This can cause your other medications to become less effective. In general, all oral medications should be administered at least 2 hours before or 2 hours after dosing of psyllium."
PetCoach has some information about psyllium use in cats.
PennState Hersheyexplains more about psyllium.
What is polyethylene glycol 3350?
antifreeze which is toxic to cats.
Both PEG3350 and lactulose (see below) are osmotic laxatives, but unlike lactulose, PEG3350 retains water in the colon rather than pulling it into the colon from the rest of the body. The US National Library of Medicineexplains more about how it works.
Comparing drugs for chronic constipation (2007) Dean L PubMed Clinical Q&A reports that PEG3350 is more effective than lactulose for treating chronic constipation in humans. Another study, Single and multiple dose pharmokinetics of polyethylene glycol (PEG3350) in healthy young and elderly subjects (2008) Pelham RW, Nix LC, Chavira RE, Cleveland M VB & Stetson P Alimentary Pharmacology & Therapeutics 28(2) pp256-65 found that it started working in some people within a day. Most people using it for their CKD cats seem to like it, finding it easy to give and effective, with no side effects.
Another advantage is that it does not have the potential to causehypercalcaemia (high calcium levels) which lactulose has, plus it is safe to give to diabetic cats.
Since PEG3350 is available over the counter, you do not need a prescription for it, though please do not use it without your vet's knowledge and approval.
MiraLAX is the most widely known brand of PEG3350 in the USA. This is a human brand which only contains PEG3350.
PEG3350 is often used in human patients to empty the bowel before an endoscopy. If you use it for this purpose, it may cause an imbalance in the body's electrolytes, particularly potassium and sodium. Therefore some varieties of PEG3350 have added electrolytes to offset the electrolyte imbalances which may result.
Since cats are not receiving PEG3350 for this purpose, the added electrolytes are not necessary, and may not be appropriate for CKD cats. Safety and palatability of polyethylene glycol 3350 as an oral laxative in cats (2011) Tam FM, Carr AP and Myers SL Journal of Feline Medicine and Surgery 13 pp694-7 used a version containing added electrolytes, and found that although it seemed to be an effective laxative in cats, it did cause increased potassium levels in some cats. These were not clinically significant, but I would recommend trying to obtain PEG3350 without added electrolytes if possible. If you have to use PEG3350 with added electrolytes, I would ask your vet to monitor your cat's potassium levels.
Safety and palatability of polyethylene glycol 3350 as an oral laxative in cats (2011) Tam FM, Carr AP and Myers SL Journal of Feline Medicine and Surgery 13 pp694-7 says "Effective doses varied widely in experimental cats, so individualized dosing is important." Since your cat may respond well to the drug, it is better to start off with a low dose and increase only as necessary.
- Plumb's Veterinary Drug Handbook states "As a laxative (extra-label): ⅛ to ¼ teaspoonful twice daily in food."
- A common starting dose is ⅛ (one eighth) of a teaspoon per day.
- If you don't see an improvement in your cat's constipation after three days, you can either give ⅛ of a teaspoon twice a day, or increase to ¼ of a teaspoon once day.
- If this doesn't work, consider giving ¼ of a teaspoon twice per day.
- If this still doesn't work, ask your vet about increasing the dose.
In humans, PEG3350 is only supposed to be given for up to seven days, but many humans and cats do use it on an ongoing basis.
Single and multiple dose pharmokinetics of polyethylene glycol (PEG3350) in healthy young and elderly subjects(2008) Pelham RW, Nix LC, Chavira RE, Cleveland M VB & Stetson P Alimentary Pharmacology & Therapeutics 28(2) pp256-65, found that 66% of the elderly people in the study had mild renal impairment but their bodies did not appear to have any problems processing the treatment compared to the other people in the study.
Feline constipation believes the warning "is a caution for humans with a tendency to self-diagnose and self-treat for months without consulting with a doctor, humans who think if a little is good, a lot is better. Provoking the Kitten equivalent of diarrhea by use of any laxative causes water and electrolyte loss which can lead to dehydration which is more risky for those with kidney disease than for healthy individuals."
The FDAinvestigated the concerns about PEG3350 and concluded "FDA decided that no action is necessary at this time based on available information."
Autism speakshas an interview with the gastroenterologist who was quoted as having concerns about PEG3350 who says "Miralax remains the most-effective medication for many children with autism and severe, chronic constipation. So if you and your pediatrician have worked through other approaches without success, I would still strongly consider using Miralax based upon current safety information. At the same time, however, I strongly recommend that the family and physician work together to find the lowest effective dose. This is true with any stool softener or other type of laxative."
Safety of polyethylene glycol 3350 solution in chronic constipation: randomized, placebo-controlled trial(2016) McGraw T Clinical and Experimental Gastroenterology 9 pp173–180 found PEG3350 was well tolerated and appeared to be safe in the human patients in the trial.
I know of hundreds of cats who have used PEG3350 over the years, some of them for years, and cannot recall any cats who had problems with it. If you are concerned, talk to your vet about the best way forward.
Drugsmentions a moderate interaction between cisapride, another treatment for constipation (see below) and PEG3350 which I am sometimes asked about. The site states "cisapride can cause an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect. The risk is increased if you have low blood levels of magnesium or potassium, which can occur with bowel cleansing preparations or excessive use of medications that have a laxative effect. Do not exceed the dose and duration of use of polyethylene glycol 3350 recommended on the product label or prescribed by your doctor."
This warning does not concern the ingredients in PEG3350 but rather the fact that PEG3350, when used for bowel cleansing, may also remove electrolytes such as potassium, and this may increase the potential risks of using cisapride. This will not apply to most cats, who are using PEG3350 but not cisapride. Even if your cat is receiving both medications, you are unlikely to be giving PEG3350 in high enough doses for this to be a problem, but discuss with your vet if you are using both products.
above).
Amazon sells MiraLAX.
Thriving Pets sells MiraLAX for US$24.95. Smaller sizes are also available.
Movicol. Unfortunately Movicol contains added electrolytes (see above).
MiraLAX used to be available on Amazon but no longer seems to be available. Your best bet is probably eBay. Suppliers change, but at the time of writing:
eBay has a seller offering 119g of MiraLAX for £25 with free delivery.
Thriving Pets sell MiraLAX for US$24.95. They will ship it to the UK but you will have to pay a customs paperwork fee of US$10, and possibly a non US credit card fee of US$5. You will also have to pay shipping and any import duties and taxes.
RestoraLAXor Lax-A-Day, and is widely available in pharmacies. Generics may also be available, but check that the product you wish to use does not have added electrolytes (see above).
Health Canadareports that some RestoraLAX lots were recalled in July 2017. If you bought your supplies before then, check the link to see if your lot is affected.
OsmoLax and Movicol. Unfortunately, as in the UK, many of these products seem to contain added electrolytes (see above), though the OsmoLax products appear to be safe (but double check the ingredients before use).
VivaLAX appears to contain the active ingredient only, but the product has disappeared from the manufacturer's website, so I suspect it has been discontinued.
What is lactulose?
The US National Library of Medicine explains more about how it works.
Lactulose and renal failure (1997) Vogt B & Frey FJ, Scandinavian Journal of Gastroenterology Supplement 222 pp100-1 indicated that lactulose may help promote the excretion of BUN and creatinine through the faeces in humans.
A more recent study, Lactulose for reduction of nitrogen products in patients with chronic kidney disease(2014) Tayebi Khosroshahi H, Habibzadeh A, Khoshbaten M, Rahbari B, Chaichi P & Badiee AH Iranian Journal of Kidney Disease 8(5) pp377-381, found that lactulose did reduce urea and creatinine levels in the human patients in the study..
The effect of lactulose supplementation on fecal microflora of patients with chronic kidney disease: a randomized clinical trial(2016) Tayebi-Khosroshahi H, Habibzadeh A, Niknafs B, Ghotaslou R, Yeganeh Sefidan F, Ghojazadeh M, Moghaddaszadeh M & Parkhide S Journal of Renal Injury Prevention 5(3) pp162–167 considers lactulose to be aprebiotic. It found that certain probiotics increased in number and creatinine levels fell in patients given lactulose.
Some people have found that lactulose also reduced creatinine levels in their CKD cats; but lactulose is not usually given specifically or solely for this purpose because of the obvious side effects of causing diarrhoea in non-constipated patients.
The British Medical JournalDrs Foster and Smith have some information about lactulose.
Duphalac), but it requires a prescription in the USA.
Chewy sells lactulose for US$14.99 with free shipping on orders over US$49.
Since lactulose is a prescription item in the USA, it can be rather expensive, but Wal-Martand Target apparentlyboth sell it for US$4 a bottle.
Kristalose is a powdered form of lactulose which can be dissolved in water, which eliminates the stickiness problem found with standard lactulose.
- Kristalose comes in packets of 10g and 20g. The 10g packet contains 15 ml of lactulose.
- Plumb's Veterinary Drug Handbook says that "one gram of the crystals is equivalent to 1.5 mL of the liquid. An anecdotal suggested dose for constipation in cats is ½ teaspoonful (2.5 ml) to ¾ teaspoonful (3.75 ml) twice daily."
- This is a daily total of lactulose of 5.0-7.5ml a day.
- This is in line with the standard lactulose dose for a 5kg (11lb) cat. If your cat is smaller than this, discuss with your vet, because as discussed above, many cats may do fine on less than this.
As with MiraLAX, you should mix it with water before giving.
If you are giving 7.5ml a day, a 10g packet would only last two days. I heard from one person who used Kristalose for her cat, but she gave up because it was so expensive.
Kristalose is available from Vet RX Direct in the USA.
hypercalcaemia (high calcium levels) after using lactulose regularly, which then improved when they stopped using lactulose. The same issue arises in humans: Effect of lactulose on calcium and magnesium absorption: a study using stable isotopes in adult men(2007) Seki N, Hamano H, Iiyama Y, Asano Y, Kokubo S, Yamauchi K, Tamura Y, Uenishi K & Kudou H Journal of Nutritional Science & Vitaminology (Tokyo) 53(1) pp5-12 found that "lactulose enhance the absorption of calcium and magnesium in adult men." You may therefore wish to avoid lactulose if your cat is already hypercalcaemic.
Although lactulose is indigestible, it is composed of sugar molecules,soMar Vista Vetadvises against using it in diabetic cats because it may raise blood sugar levels.
Drugsmentions that there is a minor interaction between lactulose andaluminium hydroxide (a phosphorus binder) which in theory may reduce the effectiveness of lactulose when it is being used to treat a condition called hepatic encephalopathy. People with CKD cats are normally using lactulose to treat constipation, not hepatic encephalopathy, so this is unlikely to be a concern. Still, if you are treating constipation caused by the use of aluminium hydroxide, and are not finding lactulose to be as effective as you hoped, you could speak to your vet about trying one of the other treatments discussed on this page instead.
Antibiotics may reduce the effectiveness of lactulose.
Lactulose may exacerbate the effects of diuretics such as furosemide.Drugshas more information about this, stating "Combining these medications, especially over a prolonged period, may increase the risk of dehydration and electrolyte abnormalities. In severe cases, dehydration and electrolyte abnormalities can lead to irregular heart rhythm, seizures, and kidney problems."
I have heard from a couple of people who found that their IBD cats did not seem to do too well on lactulose. This may be because, as mentioned in Update on the non-invasive monitoring of intestinal disease in dogs and cats(2000) Batt R Revue Médicine Véterinaire 151(7)pp559-563, more lactulose is absorbed by a damaged gut than by a healthy one. If your IBD cat seems to worsen on lactulose, speak to your vet about switching to another treatment.
