Inclusion Criteria:

For inclusion in the study, subjects must fulfil all of the following criteria: 1. Provision of informed consent. 2. Female or male aged 18 years or above. 3. Established diagnosis of MS according to McDonald criteria. 4. Patients with bowel symptoms post-dating and related to a diagnosis of MS. 5. Patients suffering from NBD symptoms defined by Wexner feacal incontinence score ≥10 and/or Cleveland Clinic constipation score ≥10 confirmed at Baseline. 6. Only TAI treatment naïve patient (not having previously used any particular TAI system). 7. Judged eligible for TAI as per standardized treatment pathway. 8. Able to read, write and understand information given to them regarding the study.

Exclusion Criteria:

Any of the following is regarded as a criterion for exclusion from the study: 1. Any confirmed or suspected diagnosis of anal or colorectal stenosis, active inflammatory bowel disease, acute diverticulitis, severe diverticulosis, colorectal cancer, ischemic colitis, history of life-threatening autonomic dysreflexia, bleeding disorders, unspecified peri-anal conditions. 2. Untreated rectal impaction. 3. Other significant neurological diseases (defined as all neurological diseases except for minor functional neurological syndromes or non-MS related neuro complications). 4. Opioid consumption ≤24 hours prior enrolment. 5. Previous colorectal surgery (including haemorrhoidectomy and fistulotomy), sphincter injury, perianal sepsis, rectal prolapse. 6. Performed endoscopic polypectomy within 4 weeks prior enrolment. 7. Ongoing, confirmed pregnancy or lactation. 8. Any neuromodulation that can affect the pelvic organ function. 9. Ongoing, symptomatic Urinary Tract Infection (UTI) at enrolment (defined as a positive urine culture of ≥10^3 CFU/ml of ≥1 bacterial species and presence of symptoms or signs compatible with UTI with no other identified source of infection).* 10. Current treatment with anticoagulants (exception acetylsalicylic acid or clopidogrel). 11. Current treatment with long-term systemic steroid medication (exception inhalation agents and/or local topical treatment). 12. Current treatment of prokinetics. 13. Involvement in the planning and conduct of the study (applies to both Wellspect HealthCare and site personnel). 14. Previous enrolment in the present study. 15. Simultaneous participation in another clinical study that may interfere with the present study as judged by the investigator. 16. Expected severe non-compliance to protocol as judged by the investigator. 17. Any other condition, as judged by the investigator, which might make follow-up or investigations inappropriate. 18. Any patient that according to the Declaration of Helsinki is unsuitable for enrolment. 19. Agranulocytosis (<0.5 10^9 / L) [Only applicable for Switzerland].

• - If symptoms and signs compatible with UTI is present but no urine culture test has been performed yet, a test should be performed, and the result received prior evaluating if the subject is eligible for study participation.

After successful and completed treatment of a UTI, the subject may be rescheduled for Visit 1 in order to re-evaluate study participation.

Arms

Experimental: Navina Smart

An electronic medical device to perform transanal irrigation. Treatment period 8 weeks.

Active Comparator: Standard Bowel Care

Supportive bowel care without using irrigation.

Interventions

Device: - Navina Smart

CE-marked NavinaTM Smart including Navina Smart App.

Other: - Standard Bowel Care

Bowel care will be scheduled at least every 2nd day according to a defined study specific standard bowel care protocol. Diet, fluids, abdominal massage, regular physical activity and medications will be used if non-interventional treatment is insufficient.