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Glycopyrrolate dries excessive salivation

Clinical Question:
Can glycopyrrolate reduce sialorrhea (drooling) in patients with Parkinson's disease?

Bottom Line:
Glycopyrrolate, 1 mg 3 times daily, is more effective than placebo in decreasing sialorrhea in patients with Parkinson's disease. It is unclear if the improvements seen in this study are clinically relevant. (LOE = 2b)

Arbouw ME, Movig KL, Koopmann M, et al. Glycopyrrolate for sialorrhea in Parkinson disease: a randomized, double-blind, crossover trial. Neurology 2010;74(15):1203-1207.  [PMID:20385892]

Study Design:
Cross-over trial (randomized)


Outpatient (specialty)

Sialorrhea, or drooling, is a common problem in patients with Parkinson's disease. It can be embarrassing and unsightly, and it can also cause skin breakdown. Many anticholinergic medications have been tried with success, but are generally not used because of their adverse central nervous system effects: sedation, confusion, and memory impairment. Glycopyrrolate, an anticholinergic agent that generally doesn't cross the blood-brain barrier, was studied in this crossover trial in 23 patients with Parkinson's disease accompanied by moderate to severe sialorrhea (at least 5 points on a self-assessed severity scale). Patients were studied for 4 weeks: 1 week without medication for baseline assessments, during which the researchers graded the severity of sialorrhea on a 9-point scale (1 = dry, never drools; 5 = moderate, frequently wet lips or chin; 9 = profuse, hands and objects frequently become wet).; 1 week with study medication (glycopyrrolate or placebo; randomly assigned); 1 week without medication as a wash-out period; and 1 week with the opposite study medication. The active medication was 1 mg (5 mL of a 0.2 mg/mL solution) given 3 times daily. The authors used the average sialorrhea severity score for the last 3 days of each treatment period. They defined a response to be a decrease in the mean score of 30% or more. They don't, however, report if this difference has been validated by patients as a clinically significant difference (and I doubt it is). A patient starting with a rating of 5 would be classified as a responder if their score went to 4.7. A more relevant response would seem to be a change in a full step in their scoring scheme. Nine of 23 patients (39.1%) were considered responders to glycopyrrolate compared with only 1 of 23 patients taking placebo (4.3%). If this response is truly clinically meaningful, then one would only need to treat 3 patients with glycopyrrolate to improve 1 patient's sialorrhea (95% CI, 2 - 10). The authors report no significant differences in side effects between glycopyrrolate and placebo. The rate of dry mouth reported by patients (52% with glycopyrrolate vs 30% with placebo), was not statistically significant but this may be more of a reflection of the small study size.


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