New contraindications have been added to the product information of Ganfort® (bimatoprost + timolol). It is now advised that these eye drops not be used in patients with sino-atrial nodal block or second or third-degree atrioventricular block not controlled with a pacemaker.
Timolol is a non-selective beta-blocker. Systemic effects of timolol may include bradycardia, orthostatic hypotension, syncope, and bronchoconstriction. While it may sometimes be assumed that eye drops do not produce significant systemic effects, studies suggest that at least 80% of an ophthalmic product drains through the nasolacrimal canal. From there, it may enter the systemic circulation while also avoiding first-pass metabolism.
The current contraindications for Ganfort® eye drops include:
- Bronchial asthma;
- Severe chronic obstructive pulmonary disease;
- Sinus bradycardia;
- Sick sinus syndrome;
- Sino-atrial nodal block;
- Second or third-degree atrioventricular block not controlled with a pacemaker;
- Overt cardiac failure; and
- Cardiogenic shock.
To avoid systemic absorption, it is recommended to immediately apply pressure to the tear duct for at least two minutes following administration of the eye drop. This is good practice for all eye drops to minimise systemic effects, avoid an unpleasant taste in the mouth, and improve retention at the site of action.
- Ganfort® (bimatoprost + timolol) Australian approved product information. Gordon: Allergan Australia. Approved October 2019.
- Müller ME, van der Velde N, Krulder JW, van der Cammen TJ. Lesson of the week: syncope and falls due to timolol eye drops. BMJ. 2006; 332(7547): 960-1.