Yes, hydroxyzine can cause dry, itchy eyes through its anticholinergic effects.
Hydroxyzine is classified as an antihistamine with anticholinergic properties, and dry mouth is explicitly listed as a known anticholinergic side effect in the FDA drug label 1. While the FDA label does not specifically mention dry eyes, the anticholinergic mechanism that causes dry mouth also affects tear production, leading to ocular dryness and associated itching.
Mechanism and Evidence
Hydroxyzine belongs to the first-generation antihistamine class, which has well-documented anticholinergic activity. The 2024 Dry Eye Syndrome guidelines explicitly identify antihistamines as systemic medications that exacerbate dry eye symptoms 2. These medications disrupt the efferent cholinergic nerves that stimulate tear secretion, leading to decreased aqueous tear production.
Supporting Research Evidence
A 2004 controlled study demonstrated that antihistamines (specifically loratadine and cetirizine) cause measurable ocular drying effects in healthy individuals, including 3:
- Increased corneal staining (keratitis)
- Increased conjunctival staining
- Decreased tear film break-up time
- Increased ocular discomfort
While this study examined second-generation antihistamines, hydroxyzine as a first-generation antihistamine has stronger anticholinergic effects, making it more likely to cause dry eye symptoms.
Clinical Implications
What to Expect:
- Dry mouth is the most commonly reported anticholinergic effect (listed in FDA label) 1
- Ocular dryness follows the same anticholinergic mechanism
- Symptoms may include dryness, itching, burning, and foreign body sensation
- Effects are typically dose-dependent and reversible
Important Caveats:
- The FDA label notes that elderly patients are particularly susceptible to anticholinergic effects and should start on low doses 1
- Patients with pre-existing dry eye disease will experience worsening symptoms
- Environmental factors (low humidity, air conditioning, screen time) compound the drying effects 2
Management Approach:
If dry, itchy eyes develop on hydroxyzine:
- Consider discontinuing or reducing the dose if clinically appropriate
- Use preservative-free artificial tears (more than 4 times daily requires preservative-free formulations) 2
- Address environmental factors
- If symptoms persist despite treatment, ophthalmology referral is warranted for moderate-to-severe cases 2
The anticholinergic drying effects are a class effect of antihistamines, with hydroxyzine being particularly prone to causing these symptoms due to its first-generation profile.