Bladder dysfunction is among the most common and perhaps also the most underestimated symptoms of MS. It can be assumed that up to 80% of those affected by MS develop problems with the bladder during the course of the disease, which often goes hand in hand with a significant reduction in quality of life. The most common form of bladder disorder – especially at the beginning of the disease – is the so-called spastic bladder (detrusor hyperreflexia). It is characterized by a restricted storage function of the bladder and manifests itself with frequent urination and an “imperative” urge to urinate – i.e., an urge to empty the bladder immediately. This situation can also occasionally result in urge incontinence, i.e., involuntary urination. Patients with detrusor hyperreflexia therefore usually look first for the nearest toilet in an unfamiliar environment – and this is definitely a significant restriction of personal freedom.
A classic cause of the spastic bladder are inflammation foci in the spinal cord that affect the descending pathways of voluntary bladder control. Simplified, this leads to a disinhibition of the bladder reflex – i.e., the bladder muscle contracts independently from a certain filling volume (filling pressure), thereby triggering the imperative urge to urinate.
Such a bladder disorder, which as already mentioned affects many patients in the early stages of the disease, is often quite accessible to drug treatment. As a rule, drugs are given that inhibit the contraction force of the bladder muscle and thus reduce the overactivity of the bladder. These drugs belong to the class of anticholinergics – i.e., they suppress the effect of the neurotransmitter acetylcholine (Ach) in the parasympathetic nervous system, which is responsible for the (reflexive) contraction of the bladder muscle. Since these drugs do not selectively affect the parasympathetic nervous system of the bladder, they cause side effects by influencing the parasympathetic nervous system of other organs. In my view, dry mouth is the most relevant side effect. Established drugs include Dridase® (oxybutynin), Detrusitol® (tolterodine) or Spasmex® (trospium chloride). The dosage and frequency per day these drugs should be used should be discussed with your treating physician.
Since the use of anticholinergics can increase residual urine volume, medication should actually only be used after a urological assessment of bladder function with determination of residual urine volume. However, pragmatically, in the early stages of the disease with isolated detrusor hyperreflexia, a therapy attempt can also be made directly.
In addition to these drug therapies, I especially recommend training the pelvic floor muscles (offered by physiotherapists) – especially in the early phases – this training can demonstrably lead to a significant reduction of the imperative urge to urinate.
By the way, a urination frequency of 4-6 times in 24 hours with urine volumes between 200 and 400 ml is considered normal – deviations from this are always a reason to speak to your neurologist and consider therapeutic measures.
