Instilling Drops in a Patient with Poor Technique and a Contaminated Bottle
An 81-year-old patient with glaucoma is seen for a follow-up. He uses latanoprost nightly and timolol twice daily. He reports that his eyes often feel irritated and that his wife "helps" by holding the bottle for him. On observation, the bottle tip touches his lashes and eyelid, and he blinks repeatedly after instillation, then wipes his eyes with a tissue. His conjunctiva is mildly hyperemic. The bottle of timolol has been open for 5 months and the tip looks cloudy. His IOP today is 24 mmHg in the right eye and 22 mmHg in the left, higher than the 17/16 recorded 6 months ago.
1. Identify the medication-handling and instillation problems you observe, and explain how each could affect IOP control or ocular surface health.
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Problems:
- Bottle tip contacting lashes/lid - contaminates the tip and can introduce organisms; also risks transferring medication between eyes.
- Blinking and wiping immediately - washes the drop out and reduces contact time, lowering absorption and IOP effect.
- Timolol bottle open 5 months with a cloudy tip - beyond typical in-use dating, possible contamination and degraded drug; a cloudy tip suggests contamination.
- Wife instilling for him - technique and drop placement may be inconsistent.
- Hyperemia - could reflect preservative toxicity (e.g., benzalkonium chloride in timolol) or irritation from frequent instillation.
Each of these reduces the effective dose reaching the eye, which fits the rise in IOP from 17/16 to 24/22. The cloudy bottle should be replaced, and technique should be retaught.
2. Describe the technique you would teach and the specific instructions for the two medications.
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Teach: wash hands; shake if suspension; tilt head back; pull lower lid to form a pocket; hold the bottle without touching the tip to any surface; instill one drop into the pocket; close the eye gently for 1-2 minutes (punctal occlusion reduces systemic absorption and nasolacrimal drainage); do not blink repeatedly or wipe; if using two drops, wait at least 5 minutes between them.
Medication-specific: latanoprost at bedtime; timolol twice daily, roughly 12 hours apart. Replace the timolol bottle (discard the old one) and check in-use dating. Consider having the wife watch a demonstration and practice under supervision. Document the teaching, the bottle replacement, and schedule an IOP recheck to confirm the effect. Note the hyperemia in the record and mention it to the physician in case a preservative-free formulation is preferred.