Timolol eye drops

Q57 Pilocarpine is a tertiary amine parasympathomimetic agent that is mainly used in the treatment of glaucoma. Pilocarpine is commonly administered with timolol eye drops. 

Backlund M, Kirvela M, Lindgren L Cardiac failure aggravated by timolol eye drops preoperative improvement by changing to pilocarpine. Acta Anaesthesiol Scand 1996 40 379-381. 

FLECAINIDE BETA-BLOCKERS Risk of bradycardia (occasionally severe), 1 BP and heart failure. Note, a single case report has described bradycardia when timolol eye drops given to a patient on flecainide Additive negative inotropic and chronotropic effects Monitor PR, BP and ECG closely watch for development of heart failure... 

BETA-BLOCKERS ANAESTHETICS-GENERAL Risk of severe hypotensive episodes during induction of anaesthesia (including patients using timolol eye drops) Most general anaesthetics are myocardial depressants and vasodilators, so additive 1 BP may occur Monitor BP closely, especially during induction of anaesthesia... 

BETA-BLOCKERS OPIOIDS 1. Risk of t plasma concentrations and effects of labetalol, metoprolol and propranolol t systemic effects of timolol eye drops 2. t plasma concentrations of esmolol when morphine is added 3. t plasma concentrations of metoprolol and propranolol when dextro-propoxyphene is added 1. Methadone inhibits CYP2D6, which metabolizes these beta-blockers 2. Unknown 3. i hepatic clearance of metoprolol and propanolol 1. Monitor BP at least weekly until stable 2. Monitor BP closely 3. Monitor BP at least weekly until stable. Warn patients to report symptoms of hypotension (lightheadedness, dizziness on standing, etc.)... 

BETA-BLOCKERS QUININE Risk oft plasma concentrations and effects of labetalol, metoprolol and propranolol t systemic effects of timolol eye drops Quinine inhibits CYP2D6, which metabolizes these beta-blockers Monitor BP at least weekly until stable... 

Glaucoma (carteolol, betaxolol, levobunolol and timolol eye drops) act by altering production and outflow of aqueous humour. 

Nausea and vomiting have been attributed to timolol eye-drops (217). 

Fetal bradycardia and pauses after each two normal beats occurred at 21 weeks gestation in a 37-year-old woman using timolol eye-drops for glaucoma when timolol was withdrawn, the fetal heart rate recovered (321). 

Wolfhagen FH, van Neerven JA, Groen FC, Ouwendijk RJ. Severe nausea and vomiting with timolol eye drops. Lancet 1998 352(9125) 373. 

An 80-year-old woman with gastrointestinal bleeding had a sinus bradycardia (52/minute) despite acute blood loss. The only drug she had used that was an AV nodal depressant was timolol maleate 0.5%, one drop to both eyes every day. Continuous electrocardiography showed transient complete AV block without ventricular escape for nearly 6 seconds about 1 hour after instillation of timolol eye drops. She also reported having previously had episodes of dizziness and occasional falls 1-2 hours after instillation of her eye drops. 

Mrs Jones brings her husband s prescription into the pharmacy. The pharmacist enters the details of the patient into the computer and realises there is a patient medication record. The prescription is for a new item that is not already on the PMR. The item ordered is timolol eye drops but there is no indication of the strength required nor are there any directions for use for the patient. 

He, H. Edeki, T.I. Wood, A.J.J. Determination of low plasma timolol concentrations following topical application of timolol eye drops in humans by high-performance liquid chromatography with electrochemical detection. J.Chromatogr.B, 1994, 661, 351-356 [LOD 0.1072 ng/mL]... 

Anaesthesia in the presence of beta blockers normally appears to be safer than withdrawal of the beta blocker before anaesthesia, provided certain inhalational anaesthetics are avoided (methosy-flurane, cyclopropane, ether, trichloroethylene) and atropine is used to prevent bradycardia. Bradycardia and marked hypotension occurred in a man using timolol eye drops when he was anaesthetised. 

A 75-year-old man being treated with timolol eye drops for glaucoma developed bradyeardia and severe hypotension when anaesthetised [drug not... 

Other case reports and studies describe heart failure, dyspnoea, - sinus arrest, heart block, "" hypotension, " and bradycar-(jj 4,5,8,io,ii,i4-i8 jjj patients taking verapamil with alprenolol, atenolol, metoprolol, " propranolof " or pindolol. In two further cases, bradycardia occurred in patients taking verapamil and using timolol eye drops. Another case has been reported, but this was complicated by the presence of flecainide , (p.844). A number of reports noted that patients experiencing this interaction had reasonable left ventricular function. Heart block and hypotension or cardiogenic shock has also been reported after verapamil was given with atenolol or propranolol in overdose. 

Pringle SD, MacEwen CJ. Severe bradycardia due to interaction of timolol eye drops and verapamil. BA47 (1987) 294, 155-6. 

The combined use of flecainide and beta blockers may have additive cardiac depressant effects. An isolated case of bradycardia and fatal AV block has been reported during the use of flecainide with sotalol, and bradycardia has been reported in a patient taking flecainide who was given timolol eye drops. 

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