DL-methionine can be used to acidify urine in some cats, but it is not a general solution for litter-box odour or every urinary problem. Whether it is appropriate depends on the diagnosis, diet and individual cat. This guide explains what to discuss with your veterinarian before using it.
Updated September 28, 2026. Educational information; this article has not been individually reviewed by a veterinarian.
What is DL-methionine used for?
Methionine is an amino acid. Supplemental methionine may be used as a urinary acidifier in selected cases. VCA’s methionine guide explains that acidifiers help manage certain urinary stones. That does not mean every cat with urinary signs needs more acidic urine.
A urinary problem needs a diagnosis
Repeated litter-box visits, pain or blood in urine can have different causes. The 2025 iCatCare lower urinary tract guidelines describe diagnosis and treatment according to the underlying condition, rather than treating all urinary signs as the same disease. A supplement cannot establish whether a cat has stones, inflammation, an infection or an obstruction.
If your cat strains and produces little or no urine, seek urgent veterinary care. Cornell identifies urinary obstruction as a medical emergency. Do not wait for a supplement to work.
Dosage and combining products
There is no one dose we can recommend for every cat. Ask your veterinarian for the exact product, amount, frequency, duration and follow-up plan. Take photographs of food and supplement labels to the appointment, including any urinary diet. Do not translate a tablet strength into a daily dose yourself.
VCA advises caution with urine-acidifying diets and lists important medical and life-stage restrictions. Tell the veterinarian about other medicines, existing illness, pregnancy or nursing before use. If a dose is missed, instructions are unclear or your cat becomes unwell, contact the prescribing practice instead of improvising or doubling a dose.
Questions to take to the appointment
- What diagnosis are we treating, and what tests support it?
- Does the current food already change urine chemistry?
- What improvement should we expect, and when should urine be rechecked?
- Which changes mean I should stop and call the practice?
Product claims and availability
A substance name alone does not establish the approval status of every product containing it. Check the exact product and country with your veterinarian. A general multivitamin is not automatically a substitute for a prescribed urinary treatment. Ragdoll Hub publishes information; we do not provide veterinary appointments or methionine treatment services.
For related reading, visit our cat health library and Ragdoll breed and care guide.