timolol

Contraindicated in:

Uncompensated HF;
Pulmonary edema;
Cardiogenic shock;
Bradycardia or heart block.

Use Cautiously in:

Renal impairment;
Hepatic impairment;
Pulmonary disease (including asthma);
Diabetes mellitus (may mask signs of hypoglycemia);
Thyrotoxicosis (may mask symptoms);
Patients with a history of severe allergic reactions (intensity of reactions may be increased);
Geri: May have ↑ sensitivity to beta blockers; initial dosage ↓ recommended);
OB: Safety not established; may cause fetal/neonatal bradycardia, hypotension, hypoglycemia, or respiratory depression.

Adv. Reactions/Side Effects ⬆ ⬇

CV: HF, ARRHYTHMIAS, BRADYCARDIA, orthostatic hypotension, peripheral vasoconstriction, PULMONARY EDEMA

Derm: itching, rashes

EENT: blurred vision, dry eyes, nasal stuffiness

Endo: hyperglycemia, hypoglycemia

GI: constipation, diarrhea, nausea

GU: erectile dysfunction, ↓libido

MS: arthralgia, back pain, muscle cramps

Neuro: fatigue, weakness, anxiety, depression, dizziness, drowsiness, insomnia, memory loss, mental status changes, nervousness, nightmares, paresthesia

Resp: bronchospasm, wheezing

Misc: ANAPHYLAXIS (RARE)

Interactions ⬆ ⬇

Drug-drug:

General anesthesia, IV phenytoin, and verapamil may ↑ myocardial depression.
↑bradycardia may occur with digoxin.
↑hypotension may occur with other antihypertensives, acute ingestion of alcohol, or nitrates.
Concurrent use with amphetamines, cocaine, ephedrine, epinephrine, norepinephrine, phenylephrine, or pseudoephedrine may result in unopposed alpha-adrenergic stimulation (excessive hypertension, bradycardia).
Concurrent thyroid administration may ↓ effectiveness.
May alter the effectiveness of insulins or oral antidiabetics (dosage adjustments may be necessary).
May ↓effectiveness of bronchodilators and theophylline.
May↓ beneficial cardiovascular effects of dopamine or dobutamine.
Use cautiously within 14 days of MAO inhibitor therapy (may result in hypertension).
Cimetidine may ↑ toxicity.
Concurrent NSAIDs may ↓ antihypertensive action.

Availability ⬆ ⬇

(Generic available)

Tablets: 5 mg; 10 mg; 20 mg

Route/Dosage ⬆ ⬇

PO (Adults ): Antihypertensive: 10 mg twice daily initially; may ↑ q 7 days as needed (usual maintenance dose is 10–20 mg twice daily; up to 60 mg/day). Prevention of MI: 10 mg twice daily, starting 1–4 wk after MI. Prevention of vascular headache: 10 mg twice daily initially, may be given as a single daily dose; may ↑ up to 10 mg in the morning and 20 mg in the evening.

US Brand Names ⬆ ⬇

Action ⬆ ⬇

Blocks stimulation of beta₁(myocardial)- and beta₂(pulmonary, vascular, and uterine)-adrenergic receptor sites.

Therapeutic effects:

Decreased heart rate and BP.
Prevention of MI.
Decreased frequency of migraine headache.

Classifications ⬆ ⬇

Therapeutic Classification: antihypertensives, vascular headache suppressants

Pharmacologic Classification: beta blockers

Pharmacokinetics ⬆ ⬇

Absorption: Well absorbed after oral administration.

Distribution: Enters breast milk.

Metabolism/Excretion: Extensively metabolized by the liver.

Half-Life: 3–4 hr.

Time/Action Profile ⬆ ⬇

(cardiovascular effects)

ROUTE	ONSET	PEAK	DURATION
PO	unknown	1–2 hr*	12–24 hr

*After single dose, full effect is not seen until several wk of therapy.

Patient/Family Teaching ⬆ ⬇

Instruct patient to take medication as directed, at the same time each day, even if feeling well; do not skip or double up on missed doses. Take missed doses as soon as possible up to 4 hr before next dose. Abrupt withdrawal may precipitate life-threatening arrhythmias, hypertension, or myocardial ischemia.
Advise patient to make sure that enough medication is available for weekends, holidays, and vacations. A written prescription may be kept in wallet in case of emergency.
Teach patient and family how to check pulse daily and BP biweekly. Advise patient to hold dose and contact health care professional if pulse is <50 bpm or BP changes significantly.
May cause drowsiness or dizziness. Caution patients to avoid driving or other activities that require alertness until response to the drug is known.
Advise patients to change positions slowly to minimize orthostatic hypotension, especially during initiation of therapy or when dose is increased.
Caution patient that this medication may increase sensitivity to cold.
Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult health care professional before taking other Rx, OTC, or herbal products, especially NSAIDs and cold preparations, concurrently with this medication.
Patients with diabetes should closely monitor blood glucose, especially if weakness, malaise, irritability, or fatigue occurs. Medication may mask tachycardia and increased BP as signs of hypoglycemia, but dizziness and sweating may still occur.
Advise patient to notify health care professional if slow pulse, difficulty breathing, wheezing, cold hands and feet, dizziness, confusion, depression, rash, fever, sore throat, unusual bleeding, or bruising occurs.
Instruct patient to inform health care professional of medication regimen before treatment or surgery.
Advise patient to carry identification describing disease process and medication regimen at all times.
Hypertension: Reinforce the need to continue additional therapies for hypertension (weight loss, sodium restriction, stress reduction, regular exercise, moderation of alcohol consumption, and smoking cessation). Medication controls but does not cure hypertension.
Vascular Headache Prophylaxis: Caution patient that sharing this medication may be dangerous.

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Indications ⬇

Contraind./Precautions ⬆ ⬇