Swallowing Therapies for Stroke Survivors: Effectiveness and Evidence Review

Swallowing therapy may improve function in stroke survivors, though no single treatment is effective for all patients, according to a review of 181 studies involving 11,500 people. The findings, current to July 2025, indicate that while various electrical stimulations and acupuncture show promise for specific outcomes, evidence for many therapies remains uncertain due to small study sizes and poor quality.

Dysphagia, or difficulty chewing and swallowing saliva, food, and drink, affects up to 80% of stroke survivors. According to the review, this condition can lead to choking, chest infections from inhaling food or saliva, malnutrition, weight loss, and prolonged hospital stays. In some cases, it increases the risk of death or the necessity of moving to a care home.

While many patients experience improvement without intervention, between 15% and 51% of survivors continue to have swallowing problems approximately two weeks after a stroke.

Effectiveness of Electrical and Nerve Stimulation

The review found that several forms of stimulation probably reduce the severity of swallowing problems. These include neuromuscular electrical stimulation (NMES) applied to the outside of the neck, transcranial direct current stimulation (tDCS) to the brain, nerve stimulation, and combined therapies.

Other stimulation methods showed mixed results. Pharyngeal electrical stimulation (PES), which targets the inside of the neck, may make little to no difference in the overall severity of swallowing problems. However, PES probably reduces the number of patients who remain dependent on a breathing tube at the end of a study.

Magnetic brain stimulation, specifically theta burst stimulation (TBS) and transcranial magnetic stimulation (TMS), may reduce the severity of swallowing problems. TMS specifically probably improves the safety of swallowing, while the effect of TBS on safety may be positive.

Outcomes for Acupuncture and Medication

Acupuncture probably results in fewer people having swallowing problems at the end of treatment and probably improves swallowing safety. The review notes that acupuncture may reduce the severity of swallowing problems, though the evidence for that specific metric is very uncertain.

Medications probably reduce the occurrence of chest infections or pneumonia. While medication may reduce the general severity of swallowing problems, the review classifies the evidence for this outcome as very uncertain.

Impact of Exercises and Physical Stimulation

Physical stimulation using fizzy drinks or cold and sour flavors may reduce the severity of swallowing problems and may result in fewer people having swallowing issues at the end of treatment. It may also reduce the number of chest infections or pneumonia cases.

Swallowing exercises may reduce the severity of swallowing problems and may improve swallowing safety. However, the review describes the evidence regarding the reduction of problem severity as very uncertain and states the effect of exercises on the need for a breathing tube is also very uncertain.

Limitations and Evidence Quality

The researchers noted significant limitations in the available data. Many of the 181 studies were small and of poor quality, which complicates the ability to trust the results. Because different therapies used varying delivery methods, it remains unclear which specific approach is most effective for each type of therapy.

The review concludes that future studies must be larger and employ more reliable methods to provide higher confidence in the results.