From the Guidelines
Glycopyrrolate commonly causes several side effects due to its anticholinergic properties, including dry mouth, blurred vision, constipation, urinary retention, and decreased sweating, which can lead to overheating, as noted in studies such as 1 and 2.
Side Effects of Glycopyrrolate
The most frequent side effects of glycopyrrolate include:
- Dry mouth
- Blurred vision
- Constipation
- Urinary retention
- Decreased sweating, which can lead to overheating Some patients may experience:
- Drowsiness
- Dizziness
- Headache
- Nervousness
- Confusion Less commonly, glycopyrrolate can cause:
- Tachycardia (increased heart rate)
- Palpitations
- Difficulty swallowing Severe side effects requiring immediate medical attention include:
- Eye pain with vision changes
- Severe constipation
- Severe stomach pain
- Difficulty urinating
- Signs of allergic reaction such as rash, itching, or swelling ### Special Considerations Elderly patients are particularly susceptible to anticholinergic side effects, especially confusion and memory problems, as mentioned in 2. These side effects occur because glycopyrrolate blocks acetylcholine receptors throughout the body, affecting various organ systems. The medication should be used with caution in patients with certain conditions, including:
- Glaucoma
- Prostatic hypertrophy
- Gastrointestinal obstructive disorders
- Myasthenia gravis Patients should stay hydrated and avoid overheating while taking this medication, especially in hot weather, as decreased sweating can impair the body's ability to regulate temperature, as noted in 1.
From the FDA Drug Label
ADVERSE REACTIONS Anticholinergics, including glycopyrrolate injection, can produce certain effects, most of which are extensions of their pharmacologic actions Adverse reactions may include xerostomia (dry mouth); urinary hesitancy and retention; blurred vision and photophobia due to mydriasis (dilation of the pupil); cycloplegia; increased ocular tension; tachycardia; palpitation; decreased sweating; loss of taste; headache; nervousness; drowsiness; weakness; dizziness; insomnia; nausea; vomiting; impotence; suppression of lactation; constipation; bloated feeling; severe allergic reactions including anaphylactic/anaphylactoid reactions; hypersensitivity; urticaria, pruritus, dry skin, and other dermal manifestations; some degree of mental confusion and/or excitement, especially in elderly persons In addition, the following adverse events have been reported from post-marketing experience with glycopyrrolate: malignant hyperthermia; cardiac arrhythmias (including bradycardia, ventricular tachycardia, ventricular fibrillation); cardiac arrest; hypertension; hypotension; seizures; and respiratory arrest Post-marketing reports have included cases of heart block and QTc interval prolongation associated with the combined use of glycopyrrolate and an anticholinesterase. Injection site reactions including pruritus, edema, erythema, and pain have also been reported
The side effects of glycopyrrolate include:
- Anticholinergic effects: xerostomia, urinary hesitancy and retention, blurred vision, cycloplegia, increased ocular tension, tachycardia, palpitation, decreased sweating, loss of taste
- Central nervous system effects: headache, nervousness, drowsiness, weakness, dizziness, insomnia, mental confusion, excitement
- Gastrointestinal effects: nausea, vomiting, constipation, bloated feeling
- Cardiovascular effects: cardiac arrhythmias, cardiac arrest, hypertension, hypotension, heart block, QTc interval prolongation
- Allergic reactions: severe allergic reactions, anaphylactic/anaphylactoid reactions, hypersensitivity, urticaria, pruritus, dry skin
- Other effects: impotence, suppression of lactation, injection site reactions, malignant hyperthermia, seizures, respiratory arrest 3
From the Research
Side Effects of Glycopyrrolate
The side effects of glycopyrrolate have been reported in several studies, including:
- Sore throat, dry mouth, and urinary retention were observed in patients who received glycopyrrolate versus those who received placebo 4
- Urinary retention and mydriasis (blurred vision) were reported in a patient who used topical glycopyrronium for axillary hyperhidrosis 5
- Mydriasis was noted within 5 min of glycopyrrolate instillation and persisted for 1 week in a study on the mydriatic effect of topical glycopyrrolate 6
- Systemic effects, such as dilation of the contralateral pupil, were observed with glycopyrrolate application, but not with soft glycopyrrolate or its analog 7
- No significant differences in adverse events were found between glycopyrrolate and placebo treatment in a study on the efficacy and safety of glycopyrrolate for sialorrhea in Parkinson disease 8
Common Side Effects
Some common side effects of glycopyrrolate include:
- Dry mouth
- Sore throat
- Urinary retention
- Mydriasis (blurred vision)
- Systemic effects, such as dilation of the contralateral pupil
Less Common Side Effects
Less common side effects of glycopyrrolate may include:
- Cardiac effects, such as changes in heart rate or blood pressure
- Gastrointestinal effects, such as constipation or nausea
- Central nervous system effects, such as drowsiness or confusion, although these are less likely due to glycopyrrolate's quaternary ammonium structure, which limits its ability to cross the blood-brain barrier 8