Does glycopyrrolate have any side effects?

October 9, 2025 •

4 min read

Glycopyrrolate is an anticholinergic medication used to treat a variety of conditions, from peptic ulcers to excessive sweating (hyperhidrosis) [1.2.4, 1.7.3]. Like all medications, it poses a risk of adverse effects. Does glycopyrrolate have any side effects? Yes, and they range from common discomforts to serious complications.

Quick Summary

Glycopyrrolate can cause a range of side effects due to its anticholinergic properties. Common issues include dry mouth, constipation, and blurred vision. Serious effects may involve urinary retention, heart issues, and heatstroke.

Key Points

Anticholinergic Action: Glycopyrrolate works by blocking acetylcholine, which leads to reduced secretions (saliva, sweat, stomach acid) and a range of side effects [1.3.2].
Common Side Effects: The most frequent side effects are dry mouth, constipation, blurred vision, urinary hesitancy, and drowsiness [1.4.1, 1.4.3].
Serious Risks: Potential serious side effects include heatstroke from decreased sweating, bowel obstruction, severe urinary retention, and acute glaucoma [1.3.4, 1.4.1].
At-Risk Populations: Individuals with glaucoma, heart disease, ulcerative colitis, or urinary obstruction should use glycopyrrolate with extreme caution or not at all [1.4.1, 1.5.3].
Management is Key: Many common side effects can be managed by drinking more water, using eye drops, and increasing fiber intake [1.6.1, 1.6.3].
CNS Effects: Compared to other anticholinergics like oxybutynin, glycopyrrolate is less likely to cause central nervous system side effects like confusion because it doesn't cross the blood-brain barrier as easily [1.3.1, 1.11.1].
Medical Supervision: It is crucial to take the medication as prescribed and report any severe or persistent side effects to a healthcare provider immediately [1.5.2].

Understanding Glycopyrrolate and Its Mechanism

Glycopyrrolate is a medication belonging to the class of drugs known as anticholinergics [1.2.4]. It works by blocking the action of acetylcholine, a neurotransmitter responsible for stimulating various bodily functions [1.3.2]. By inhibiting acetylcholine at muscarinic receptors, glycopyrrolate can decrease stomach acid production, reduce saliva and sweat, and slow gastrointestinal motility [1.3.2, 1.3.3]. This mechanism makes it useful for several conditions, including:

Peptic Ulcers: To reduce stomach acid in conjunction with other treatments [1.2.5].
Hyperhidrosis (Excessive Sweating): Used off-label to decrease sweat production, available in oral and topical forms [1.7.3, 1.7.1].
Chronic Drooling: To reduce saliva in children with neurological conditions like cerebral palsy [1.2.3].
Chronic Obstructive Pulmonary Disease (COPD): Inhaled formulations help maintain airflow by acting as a bronchodilator [1.2.1, 1.8.4].
Perioperatively: To reduce salivary and respiratory secretions and manage heart rate during surgery [1.2.1].

Because acetylcholine receptors are found throughout the body, blocking them can lead to a wide array of side effects [1.6.1].

Common Side Effects of Glycopyrrolate

Many users of glycopyrrolate experience mild to moderate side effects. These are typically predictable consequences of its anticholinergic action. The most frequently reported side effects include:

Dry Mouth: One of the most common side effects [1.4.1, 1.10.1].
Constipation: Slowed gastrointestinal motility often leads to constipation [1.4.3, 1.10.1].
Blurred Vision and Dry Eyes: The medication can affect tear production and the muscles that focus the eyes [1.4.3, 1.6.1].
Urinary Hesitancy and Retention: Difficulty starting urination or completely emptying the bladder is common [1.10.1].
Decreased Sweating: This is the intended effect for hyperhidrosis treatment but a side effect for other uses. It can lead to overheating [1.4.1].
Drowsiness, Dizziness, and Headache: CNS effects can impair mental alertness [1.2.4, 1.4.1].
Flushing: Redness of the face and neck [1.4.3].
Nausea and Vomiting: Some users experience gastrointestinal upset [1.2.4].

Serious Side Effects and Risks

While less common, glycopyrrolate can cause severe adverse reactions that require immediate medical attention. It is crucial to be aware of these risks, especially for individuals with pre-existing conditions.

Heat Prostration and Heatstroke: Due to decreased sweating, the body's ability to cool itself is impaired. This is particularly dangerous in hot environments or during physical exercise [1.2.2, 1.4.1]. Symptoms include fever, red and hot skin, and decreased alertness [1.5.4].
Bowel Obstruction (Paralytic Ileus): The slowing of intestinal movement can, in rare cases, lead to a complete blockage [1.3.4, 1.5.2]. Paradoxically, diarrhea can be an early symptom of an incomplete obstruction [1.5.5].
Severe Urinary Retention: Inability to urinate is a medical emergency [1.5.2].
Cardiovascular Effects: Glycopyrrolate can cause a rapid heartbeat (tachycardia), palpitations, and changes in blood pressure. It should be used with caution in patients with heart disease [1.3.1, 1.3.2].
Cognitive and Vision Changes: Confusion, hallucinations (especially in the elderly), and severe blurred vision can occur [1.2.2, 1.3.4]. Glycopyrrolate may also precipitate acute glaucoma in susceptible individuals, causing severe eye pain and redness [1.3.4].
Allergic Reactions: Symptoms like skin rash, hives, and swelling of the face, lips, or tongue require immediate medical help [1.4.3].

Comparison of Glycopyrrolate and Oxybutynin Side Effects

Oxybutynin is another anticholinergic drug sometimes used for hyperhidrosis. While they share many side effects, there are key differences. Glycopyrrolate, being a quaternary amine, does not cross the blood-brain barrier as easily as oxybutynin [1.3.1, 1.11.1]. This generally results in fewer central nervous system side effects like drowsiness and confusion for glycopyrrolate users [1.11.1, 1.11.3].


Feature/Side Effect	Glycopyrrolate	Oxybutynin
Primary Uses	Peptic ulcers, drooling, COPD, hyperhidrosis (off-label) [1.2.4, 1.7.3]	Overactive bladder, hyperhidrosis (off-label) [1.11.4]
CNS Side Effects	Less common (e.g., drowsiness, confusion) [1.11.1]	More common (e.g., drowsiness, confusion, hallucinations) [1.11.1]
Common Side Effects	Dry mouth, constipation, blurred vision, urinary hesitancy [1.4.1]	Dry mouth, constipation, dizziness, sleepiness [1.11.4]
Mechanism	Blocks acetylcholine receptors; does not easily cross blood-brain barrier [1.3.1]	Blocks acetylcholine receptors; penetrates the CNS more easily [1.11.1]

Managing Glycopyrrolate Side Effects

Many of the common side effects can be managed with simple lifestyle adjustments [1.6.1]:

For Dry Mouth: Drink plenty of water, chew sugarless gum, or suck on hard candy [1.6.3].
For Constipation: Increase dietary fiber and fluid intake, and exercise regularly [1.6.4].
For Dry Eyes: Use over-the-counter lubricating eye drops [1.6.1].
To Avoid Overheating: Avoid strenuous activity in hot weather and stay well-hydrated [1.6.3].

It is essential to take glycopyrrolate exactly as prescribed. For some forms, taking it on an empty stomach (1 hour before or 2 hours after meals) is recommended [1.2.4]. Do not drive or operate heavy machinery until you know how the medication affects you [1.4.3]. Always discuss any bothersome or severe side effects with a healthcare provider, who may adjust the dose [1.6.1].

Conclusion

So, does glycopyrrolate have any side effects? Yes, it has a well-documented profile of adverse effects stemming from its anticholinergic properties. While common side effects like dry mouth and constipation are often manageable, the risk of serious complications such as heatstroke, bowel obstruction, and severe urinary retention necessitates caution. Patients with pre-existing conditions like glaucoma, heart disease, or urinary issues are at higher risk [1.4.3, 1.5.3]. Understanding these potential effects and maintaining open communication with a healthcare provider are key to using glycopyrrolate safely and effectively.

For more detailed information, consult the resources at the National Library of Medicine (MedlinePlus) [1.5.4].

Frequently Asked Questions

The most common side effects include dry mouth, blurred vision, constipation, drowsiness, flushing, headache, and difficulty urinating [1.4.1, 1.4.3].

Yes. Glycopyrrolate reduces your body's ability to sweat, which can lead to overheating, fever, and potentially life-threatening heatstroke, especially in hot weather or during exercise [1.2.2, 1.4.1].

Long-term use should be monitored by a doctor. While many use it for chronic conditions like COPD, potential side effects like constipation or urinary issues can persist or worsen over time [1.5.5, 1.10.1]. Your healthcare provider can assess the risks and benefits for your specific situation.

Yes, glycopyrrolate can cause cardiovascular side effects such as a fast heartbeat (tachycardia) and palpitations. It should be used with caution in patients who have pre-existing heart conditions like coronary artery disease or arrhythmias [1.3.2, 1.3.1].

To manage dry mouth, it helps to drink plenty of water, chew sugarless gum, or suck on hard candies or ice chips. Over-the-counter saliva substitutes can also provide relief [1.4.1, 1.6.3].

You should avoid driving, operating heavy machinery, or doing other hazardous tasks until you know how glycopyrrolate affects you, as it can cause drowsiness and blurred vision [1.2.4]. Also, avoid strenuous activities in hot weather to prevent overheating [1.2.2].

Signs of a serious side effect include severe stomach cramping with inability to pass gas or stool, inability to urinate, eye pain with redness, fever with a lack of sweating, and allergic reactions like hives or swelling of the throat [1.4.3, 1.3.4, 1.5.2].