Hypersensitivity to catecholamines has been observed in patients withdrawn from beta-blocker therapy; exacerbation of angina and, in some cases, myocardial infarction have occurred after abrupt discontinuation of such therapy. When discontinuing chronically administered timolol, particularly in patients with ischemic heart disease, gradually reduce the dosage over a period of one to two weeks and carefully monitor the patient. If angina markedly worsens or acute coronary insufficiency develops, reinstitute timolol administration promptly, at least temporarily, and take other measures appropriate for the management of unstable angina. Warn patients against interruption of discontinuation of therapy without the physician's advice. Because coronary artery disease is common and may be unrecognized, it may be prudent not to discontinue timolol therapy abruptly, even in patients treated only for hypertension.
Hypertension (alternative agent):
Note: Not recommended in the absence of specific comorbidities (eg, ischemic heart disease, arrhythmia) (Ref).
Oral: Initial: 10 mg twice daily; adjust dose based on patient response at intervals of ≥7 days; usual dosage: 20 to 40 mg/day in 2 divided doses; maximum dose: 60 mg/day in 2 divided doses.
Migraine, prevention:
Note: An adequate trial for assessment of effect is considered to be at least 2 to 3 months at a therapeutic dose (Ref).
Oral: Initial: 5 mg once daily; may increase dose based on response and tolerability. Usual dosage range: 10 to 30 mg/day in 2 divided doses; maximum: 30 mg/day (Ref).
Myocardial infarction, secondary prevention:
Note: An oral beta-blocker is recommended within the first 24 hours for most patients. Patients who did not receive a beta-blocker within 24 hours of myocardial infarction should be reevaluated for secondary prevention at a later date (Ref).
Oral: Initial: 5 mg twice daily; may increase to a target dose of 10 mg twice daily (Ref). The optimal duration of therapy is unknown; reassess need for long-term beta-blocker use (>1 year) if no other primary indication exists (eg, angina, arrhythmia, hypertension) (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no specific dosage adjustments provided in the manufacturer’s labeling. However, timolol is primarily eliminated renally; dosage reduction may be necessary. Significant hypotension has been seen in patients with severe impairment and undergoing dialysis. Use with caution.
There are no specific dosage adjustments provided in the manufacturer’s labeling. However, timolol is partially metabolized by the liver; dosage reduction may be necessary.
Refer to adult dosing.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
1% to 10%:
Cardiovascular: Bradycardia (5% to 9%), cardiac arrhythmia (1%), cold extremity (8%), heart failure (8%), hypotension (3%)
Dermatologic: Pruritus (1%)
Gastrointestinal: GI adverse effects (≤8%; including nausea)
Nervous system: Asthenia (≤5%), dizziness (2% to 6%), fatigue (≤5%)
Ophthalmic: Eye irritation (1%)
Respiratory: Bronchial obstruction (2%), dyspnea (2%), pulmonary edema (2%)
<1%:
Cardiovascular: Chest pain, syncope
Endocrine & metabolic: Decreased libido
Nervous system: Paresthesia, vertigo
Otic: Tinnitus
Respiratory: Bronchospasm, rales
Frequency not defined:
Endocrine & metabolic: Decreased HDL cholesterol, increased serum potassium, increased serum triglycerides, increased uric acid
Hematologic & oncologic: Decreased hematocrit, decreased hemoglobin
Renal: Increased blood urea nitrogen
Postmarketing:
Cardiovascular: Arterial insufficiency (exacerbation), exacerbation of angina pectoris, palpitations, Raynaud disease, vasodilation
Dermatologic: Alopecia, diaphoresis, skin hyperpigmentation, skin irritation, skin rash
Endocrine & metabolic: Hyperglycemia, hypoglycemia, weight loss
Gastrointestinal: Diarrhea, dyspepsia, gastrointestinal pain, vomiting
Genitourinary: Difficulty in micturition, erectile dysfunction, retroperitoneal fibrosis
Hematologic & oncologic: Nonthrombocytopenic purpura
Hepatic: Hepatomegaly, increased liver enzymes
Hypersensitivity: Anaphylaxis
Nervous system: Cerebrovascular accident, depression, drowsiness, exacerbation of myasthenia gravis, hallucination, insomnia, lack of concentration, nervousness, nightmares
Neuromuscular & skeletal: Arthralgia, lower extremity pain, upper extremity pain
Ophthalmic: Blepharoptosis, diplopia, dry eye syndrome (Frais 1979), visual disturbance
Respiratory: Cough
Miscellaneous: Decreased exercise tolerance, fever
Hypersensitivity to timolol or any component of the formulation; sinus bradycardia; second- or third-degree heart block (except in patients with a functioning artificial pacemaker); cardiogenic shock; overt cardiac failure; bronchial asthma (or history of); severe chronic obstructive pulmonary disease.
Canadian labeling: Additional contraindications (not in US labeling): Right ventricular failure secondary to pulmonary hypertension; significant cardiomegaly; allergic rhinitis; anesthesia with agents that produce myocardial depression (eg, ether hypersensitivity to timolol maleate).
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Concerns related to adverse events:
• Anaphylactic reactions: Use caution with history of severe anaphylaxis to allergens; patients taking beta-blockers may become more sensitive to repeated challenges. Treatment of anaphylaxis (eg, epinephrine) in patients taking beta-blockers may be ineffective or promote undesirable effects.
Disease-related concerns:
• Bronchospastic disease: In general, patients with bronchospastic disease should not receive beta-blockers; if used at all, should be used cautiously with close monitoring.
• Conduction abnormality: Consider preexisting conditions such as sick sinus syndrome before initiating.
• Diabetes: Use with caution in patients with diabetes mellitus; may potentiate hypoglycemia and/or mask signs and symptoms.
• Heart failure: Use with caution in patients with compensated heart failure and monitor for a worsening of the condition.
• Myasthenia gravis: Use with caution in patients with myasthenia gravis; can worsen.
• Peripheral vascular disease (PVD) and Raynaud disease: Can precipitate or aggravate symptoms of arterial insufficiency in patients with PVD and Raynaud disease. Use with caution and monitor for progression of arterial obstruction.
• Pheochromocytoma (untreated): Adequate alpha-blockade is required prior to use of any beta-blocker.
• Psoriasis: Beta-blocker use has been associated with induction or exacerbation of psoriasis, but cause and effect have not been firmly established.
• Renal impairment: Use with caution in patients with severe renal impairment; marked hypotension can occur in patients maintained on hemodialysis.
• Thyroid disease: May mask signs of hyperthyroidism (eg, tachycardia). If thyrotoxicosis is suspected, carefully manage and monitor; abrupt withdrawal may exacerbate symptoms of hyperthyroidism or precipitate thyroid storm.
• Vasospastic angina: Beta-blockers without alpha1-adrenergic receptor blocking activity should be avoided in patients with Prinzmetal variant angina since unopposed alpha1-adrenergic receptors mediate coronary vasoconstriction and can worsen anginal symptoms (Mayer 1998).
Special populations:
• Older adults: Bradycardia may be observed more frequently in patients >65 years of age; dosage reductions may be necessary.
Other warnings/precautions:
• Abrupt withdrawal: [US Boxed Warning]: Beta-blocker therapy should not be withdrawn abruptly (particularly in patients with CAD), but gradually tapered to avoid acute tachycardia, hypertension, and/or ischemia. Severe exacerbation of angina, ventricular arrhythmias, and myocardial infarction (MI) have been reported following abrupt withdrawal of beta-blocker therapy. Temporary but prompt resumption of beta-blocker therapy may be indicated with worsening of angina or acute coronary insufficiency.
• Major surgery: Chronic beta-blocker therapy should not be routinely withdrawn prior to major surgery.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral, as maleate:
Generic: 5 mg, 10 mg, 20 mg
Yes
Tablets (Timolol Maleate Oral)
5 mg (per each): $1.32 - $1.38
10 mg (per each): $1.63 - $1.70
20 mg (per each): $3.02 - $3.14
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral, as maleate:
Generic: 5 mg, 10 mg, 20 mg
Oral: Administer with food at the same time each day.
Hypertension: Management of hypertension. Note: Beta-blockers are not recommended as first-line therapy (ACC/AHA [Whelton 2018]).
Migraine, prevention: Prevention of migraine.
Myocardial infarction, secondary prevention: To reduce mortality following MI.
Timolol may be confused with atenolol, Tylenol
Substrate of CYP2D6 (Major); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential;
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Acetylcholinesterase Inhibitors: May increase bradycardic effects of Beta-Blockers. Risk C: Monitor
Ajmaline: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Alfuzosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Alpha2-Agonists: Beta-Blockers may increase rebound hypertensive effects of Alpha2-Agonists. This effect can occur when the Alpha2-Agonist is abruptly withdrawn. Alpha2-Agonists may increase AV-blocking effects of Beta-Blockers. Sinus node dysfunction may also be enhanced. Management: Closely monitor heart rate during treatment with a beta blocker and clonidine. Withdraw beta blockers several days before clonidine withdrawal when possible, and monitor blood pressure closely. Recommendations for other alpha2-agonists are unavailable. Risk D: Consider Therapy Modification
Amifostine: Blood Pressure Lowering Agents may increase hypotensive effects of Amifostine. Management: When used at chemotherapy doses, hold blood pressure lowering medications for 24 hours before amifostine administration. If blood pressure lowering therapy cannot be held, do not administer amifostine. Use caution with radiotherapy doses of amifostine. Risk D: Consider Therapy Modification
Amiodarone: May increase bradycardic effects of Beta-Blockers. Possibly to the point of cardiac arrest. Amiodarone may increase serum concentration of Beta-Blockers. Risk C: Monitor
Amphetamines: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Antidiabetic Agents: Beta-Blockers (Nonselective) may increase hypoglycemic effects of Antidiabetic Agents. Beta-Blockers (Nonselective) may increase adverse/toxic effects of Antidiabetic Agents. Specifically, beta-blockers may mask the hypoglycemic symptoms of antidiabetic agents. Risk C: Monitor
Antipsychotic Agents (Phenothiazines): May increase hypotensive effects of Beta-Blockers. Beta-Blockers may decrease metabolism of Antipsychotic Agents (Phenothiazines). Antipsychotic Agents (Phenothiazines) may decrease metabolism of Beta-Blockers. Risk C: Monitor
Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may increase hypotensive effects of Antipsychotic Agents (Second Generation [Atypical]). Risk C: Monitor
Arginine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Artemether and Lumefantrine: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Barbiturates: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Benperidol: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Beta2-Agonists: Beta-Blockers (Nonselective) may decrease bronchodilatory effects of Beta2-Agonists. Risk X: Avoid
Bradycardia-Causing Agents: May increase bradycardic effects of Bradycardia-Causing Agents. Risk C: Monitor
Brigatinib: May decrease antihypertensive effects of Antihypertensive Agents. Brigatinib may increase bradycardic effects of Antihypertensive Agents. Risk C: Monitor
Brimonidine (Topical): May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Bromperidol: May decrease hypotensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase hypotensive effects of Bromperidol. Risk X: Avoid
Cafedrine: May increase bradycardic effects of Beta-Blockers. Beta-Blockers may decrease therapeutic effects of Cafedrine. Risk C: Monitor
Cannabis: Beta-Blockers may increase adverse/toxic effects of Cannabis. Specifically, the risk of hypoglycemia may be increased. Risk C: Monitor
Ceritinib: Bradycardia-Causing Agents may increase bradycardic effects of Ceritinib. Management: If this combination cannot be avoided, monitor patients for evidence of symptomatic bradycardia, and closely monitor blood pressure and heart rate during therapy. Risk D: Consider Therapy Modification
Cholinergic Agonists: Beta-Blockers may increase adverse/toxic effects of Cholinergic Agonists. Of particular concern are the potential for cardiac conduction abnormalities and bronchoconstriction. Risk C: Monitor
CYP2D6 Inhibitors (Moderate): May increase serum concentration of Timolol (Systemic). Risk C: Monitor
CYP2D6 Inhibitors (Strong): May increase serum concentration of Timolol (Systemic). Risk C: Monitor
Dexmethylphenidate: May decrease therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Diazoxide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Dipyridamole: May increase bradycardic effects of Beta-Blockers. Risk C: Monitor
Disopyramide: May increase bradycardic effects of Beta-Blockers. Beta-Blockers may increase negative inotropic effects of Disopyramide. Risk C: Monitor
DOBUTamine: Beta-Blockers may decrease therapeutic effects of DOBUTamine. Risk C: Monitor
Dronedarone: May increase bradycardic effects of Beta-Blockers. Dronedarone may increase serum concentration of Beta-Blockers. This likely applies only to those agents that are metabolized by CYP2D6. Management: Use lower initial beta-blocker doses; adequate tolerance of the combination, based on ECG findings, should be confirmed prior to any increase in beta-blocker dose. Increase monitoring for clinical response and adverse effects. Risk D: Consider Therapy Modification
DULoxetine: Blood Pressure Lowering Agents may increase hypotensive effects of DULoxetine. Risk C: Monitor
EPHEDrine (Systemic): Beta-Blockers may decrease therapeutic effects of EPHEDrine (Systemic). Risk C: Monitor
EPINEPHrine (Nasal): Beta-Blockers (Nonselective) may increase hypertensive effects of EPINEPHrine (Nasal). Risk C: Monitor
EPINEPHrine (Oral Inhalation): Beta-Blockers (Nonselective) may increase hypertensive effects of EPINEPHrine (Oral Inhalation). Risk C: Monitor
EPINEPHrine (Systemic): Beta-Blockers (Nonselective) may increase hypertensive effects of EPINEPHrine (Systemic). Risk C: Monitor
Ergot Derivatives (Vasoconstrictive CYP3A4 Substrates): Beta-Blockers may increase vasoconstricting effects of Ergot Derivatives (Vasoconstrictive CYP3A4 Substrates). Risk C: Monitor
Etilefrine: Beta-Blockers may decrease therapeutic effects of Etilefrine. Etilefrine may increase bradycardic effects of Beta-Blockers. Risk C: Monitor
Etofylline: Beta-Blockers may decrease therapeutic effects of Etofylline. Risk X: Avoid
Etrasimod: May increase bradycardic effects of Bradycardia-Causing Agents. Risk C: Monitor
Fexinidazole: Bradycardia-Causing Agents may increase arrhythmogenic effects of Fexinidazole. Risk X: Avoid
Fingolimod: Bradycardia-Causing Agents may increase bradycardic effects of Fingolimod. Management: Consult with the prescriber of any bradycardia-causing agent to see if the agent could be switched to an agent that does not cause bradycardia prior to initiating fingolimod. If combined, perform continuous ECG monitoring after the first fingolimod dose. Risk D: Consider Therapy Modification
Flunarizine: May increase therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Grass Pollen Allergen Extract (5 Grass Extract): Beta-Blockers may increase adverse/toxic effects of Grass Pollen Allergen Extract (5 Grass Extract). More specifically, Beta-Blockers may inhibit the ability to effectively treat severe allergic reactions to Grass Pollen Allergen Extract (5 Grass Extract) with epinephrine. Some other effects of epinephrine may be unaffected or even enhanced (e.g., vasoconstriction) during treatment with Beta-Blockers. Management: Consider alternatives to either grass pollen allergen extract (5 grass extract) or beta-blockers in patients with indications for both agents. Canadian product labeling specifically lists this combination as contraindicated. Risk D: Consider Therapy Modification
Herbal Products with Blood Pressure Increasing Effects: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Herbal Products with Blood Pressure Lowering Effects: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Hypotension-Associated Agents: Blood Pressure Lowering Agents may increase hypotensive effects of Hypotension-Associated Agents. Risk C: Monitor
Iloperidone: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Indoramin: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Insulin: Beta-Blockers (Nonselective) may increase hypoglycemic effects of Insulin. Beta-Blockers (Nonselective) may decrease therapeutic effects of Insulin. Risk C: Monitor
Isocarboxazid: May increase antihypertensive effects of Antihypertensive Agents. Risk X: Avoid
Isoproterenol: Beta-Blockers may decrease therapeutic effects of Isoproterenol. Risk C: Monitor
Ivabradine: Bradycardia-Causing Agents may increase bradycardic effects of Ivabradine. Risk C: Monitor
Lacosamide: Bradycardia-Causing Agents may increase AV-blocking effects of Lacosamide. Risk C: Monitor
Landiolol: Bradycardia-Causing Agents may increase bradycardic effects of Landiolol. Risk X: Avoid
Levodopa-Foslevodopa: Blood Pressure Lowering Agents may increase hypotensive effects of Levodopa-Foslevodopa. Risk C: Monitor
Loop Diuretics: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Lormetazepam: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Mavacamten: Beta-Blockers may increase adverse/toxic effects of Mavacamten. Specifically, negative inotropic effects may be increased. Risk C: Monitor
Mavorixafor: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk X: Avoid
Metergoline: May decrease antihypertensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase orthostatic hypotensive effects of Metergoline. Risk C: Monitor
Methacholine: Beta-Blockers may increase adverse/toxic effects of Methacholine. Risk C: Monitor
Methylphenidate: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Midodrine: May increase bradycardic effects of Bradycardia-Causing Agents. Risk C: Monitor
Mivacurium: Beta-Blockers may increase therapeutic effects of Mivacurium. Risk C: Monitor
Molsidomine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Naftopidil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicergoline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicorandil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
NIFEdipine (Topical): May increase adverse/toxic effects of Beta-Blockers. Risk C: Monitor
NIFEdipine: May increase hypotensive effects of Beta-Blockers. NIFEdipine may increase negative inotropic effects of Beta-Blockers. Risk C: Monitor
Nitrendipine: May increase therapeutic effects of Beta-Blockers. Risk C: Monitor
Nitroprusside: Blood Pressure Lowering Agents may increase hypotensive effects of Nitroprusside. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents (Topical): May decrease therapeutic effects of Beta-Blockers. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents: May decrease antihypertensive effects of Beta-Blockers. Risk C: Monitor
Obinutuzumab: May increase hypotensive effects of Blood Pressure Lowering Agents. Management: Consider temporarily withholding blood pressure lowering medications beginning 12 hours prior to obinutuzumab infusion and continuing until 1 hour after the end of the infusion. Risk D: Consider Therapy Modification
Opipramol: Beta-Blockers may increase serum concentration of Opipramol. Opipramol may increase serum concentration of Beta-Blockers. Risk C: Monitor
Ozanimod: May increase bradycardic effects of Bradycardia-Causing Agents. Risk C: Monitor
Peginterferon Alfa-2b: May decrease serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Peginterferon Alfa-2b may increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Pentoxifylline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Perazine: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
PHENobarbital: May increase hypotensive effects of Timolol (Systemic). PHENobarbital may decrease serum concentration of Timolol (Systemic). Risk C: Monitor
Pholcodine: Blood Pressure Lowering Agents may increase hypotensive effects of Pholcodine. Risk C: Monitor
Phosphodiesterase 5 Inhibitors: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Ponesimod: Bradycardia-Causing Agents may increase bradycardic effects of Ponesimod. Management: Avoid coadministration of ponesimod with drugs that may cause bradycardia when possible. If combined, monitor heart rate closely and consider obtaining a cardiology consult. Do not initiate ponesimod in patients on beta-blockers if HR is less than 55 bpm. Risk D: Consider Therapy Modification
Prazosin: Antihypertensive Agents may increase hypotensive effects of Prazosin. Risk C: Monitor
Prostacyclin Analogues: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Quinagolide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Reserpine: May increase hypotensive effects of Beta-Blockers. Reserpine may increase bradycardic effects of Beta-Blockers. Risk C: Monitor
Rivastigmine: May increase bradycardic effects of Beta-Blockers. Risk X: Avoid
Silodosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Siponimod: Bradycardia-Causing Agents may increase bradycardic effects of Siponimod. Management: Avoid coadministration of siponimod with drugs that may cause bradycardia. If combined, consider obtaining a cardiology consult regarding patient monitoring. Risk D: Consider Therapy Modification
Succinylcholine: Beta-Blockers may increase neuromuscular-blocking effects of Succinylcholine. Risk C: Monitor
Sulfonylureas: Beta-Blockers (Nonselective) may increase hypoglycemic effects of Sulfonylureas. Beta-Blockers (Nonselective) may decrease therapeutic effects of Sulfonylureas. Risk C: Monitor
Tasimelteon: Beta-Blockers may decrease therapeutic effects of Tasimelteon. Management: Consider avoiding nighttime administration of beta-blockers during tasimelteon therapy due to the potential for reduced tasimelteon efficacy. Risk D: Consider Therapy Modification
Terazosin: Antihypertensive Agents may increase hypotensive effects of Terazosin. Risk C: Monitor
Theodrenaline: May increase bradycardic effects of Beta-Blockers. Beta-Blockers may decrease therapeutic effects of Theodrenaline. Risk C: Monitor
Theophylline Derivatives: Beta-Blockers (Nonselective) may decrease bronchodilatory effects of Theophylline Derivatives. Risk C: Monitor
Urapidil: Antihypertensive Agents may increase hypotensive effects of Urapidil. Risk C: Monitor
White Birch Allergen Extract: Beta-Blockers may increase adverse/toxic effects of White Birch Allergen Extract. Specifically, beta-blockers may reduce the effectiveness of beta-agonists that may be required to treat systemic reactions to white birch allergen extract. Risk X: Avoid
Medications considered acceptable for the treatment of chronic hypertension during pregnancy may generally be used in patients trying to conceive. Timolol is not considered a preferred agent for use in pregnant patients; consider transitioning to a preferred agent in patients planning to become pregnant (ACC/AHA [Whelton 2018]; ACOG 2019).
Timolol is approved for prevention of migraines. In general, preventive treatment for migraine in patients trying to become pregnant should be avoided. Options for patients planning a pregnancy should be considered as part of a shared decision-making process. Nonpharmacologic interventions should be considered initially. When needed, preventive treatment should be individualized considering the available safety data and needs of the patient should pregnancy occur. A gradual discontinuation of preventive medications is generally preferred when the decision is made to stop treatment prior to conception (ACOG 2022; AHS [Ailani 2021]).
Decreased libido and impotence are noted in product labeling following use of timolol. As a class, outcomes from available studies evaluating beta-blockers and sexual dysfunction are inconsistent, and the negative effects on erectile function and libido are considered controversial. A clear relationship between use of beta-blockers and erectile dysfunction has not been established. Hypertension itself is associated with erectile dysfunction. Patients on a beta-blocker presenting with sexual dysfunction should be evaluated for underlying disease (Farmakis 2021; Levine 2012; Semet 2017; Terentes-Printzios 2022; Viigimaa 2020).
Timolol crosses the placenta (Schneider 1988).
Exposure to beta-blockers during pregnancy may increase the risk for adverse events in the neonate. Decreased fetal heart rate has been observed following maternal use of timolol during pregnancy (Devoe 1986). If maternal use of a beta-blocker is needed, monitor fetal growth during pregnancy; monitor the newborn for 48 hours after delivery for bradycardia, hypoglycemia, and respiratory depression (ESC [Regitz-Zagrosek 2018]).
Chronic maternal hypertension is also associated with adverse events in the fetus/infant. Chronic maternal hypertension may increase the risk of birth defects, low birth weight, premature delivery, stillbirth, and neonatal death. Actual fetal/neonatal risks may be related to the duration and severity of maternal hypertension. Untreated chronic hypertension may also increase the risks of adverse maternal outcomes, including gestational diabetes, preeclampsia, delivery complications, stroke, and myocardial infarction (ACOG 2019).
Patients with preexisting hypertension may continue their medication during pregnancy unless contraindications exist (ESC [Regitz-Zagrosek 2018]). When treatment of hypertension is initiated during pregnancy, agents other than timolol may be preferred (ACOG 2019; ESC [Cífková 2020]; ESC [Regitz-Zagrosek 2018]; SOGC [Magee 2022]).
In general, preventive treatment for migraine should be avoided during pregnancy. Options for pregnant patients should be considered as part of a shared decision-making process. Nonpharmacologic interventions should be considered initially. When needed, preventive treatment should be individualized considering the available safety data, the potential for adverse maternal and fetal events, and needs of the patient (ACOG 2022; AHS [Ailani 2021]). If preventive therapy is needed, beta-blockers may be considered (ACOG 2022) however agents other than timolol are preferred (CHS [Pringsheim 2012]).
Timolol is present in breast milk.
Based on data obtained following maternal use of ophthalmic timolol, it is recommended that breastfeeding infants (especially those with cardiorespiratory problems) be monitored for adverse events (Madadi 2008).
Due to the potential for serious adverse reactions in the breastfed infant, the manufacturer recommends a decision be made whether to discontinue breastfeeding or the drug, considering the importance of treatment to the mother.
When treatment for hypertension is needed in a breastfeeding patient, consider use of an agent other than timolol (ACOG 2019).
In general, preventive treatment for migraine in lactating patients should be avoided. When needed, therapy should be individualized considering the available safety data and needs of the patient (AHS [Ailani 2021]).
Should be administered with food at the same time each day.
Blood pressure, heart rate; ECG; mental alertness; signs and symptoms of bronchospasm in patients with existing bronchospastic disease; serum glucose (in patients with diabetes).
Blood pressure goal: May vary depending on clinical conditions, different clinical practice guidelines, and expert opinion. Refer to "Clinical Practice Guidelines" for specific treatment goals.
Blocks both beta1- and beta2-adrenergic receptors; reduces blood pressure by blocking adrenergic receptors and decreasing sympathetic outflow, produces a negative chronotropic and inotropic activity through an unknown mechanism
Onset of action: Hypotensive: 15 to 45 minutes
Peak effect: 0.5 to 2.5 hours
Duration: ~4 hours
Absorption: Rapid and complete (~90%)
Distribution: Vd: 1.7 L/kg
Protein binding: 60%
Metabolism: Extensively hepatic via CYP2D6; extensive first-pass effect
Bioavailability: 50%
Half-life elimination: 2 to 2.7 hours; prolonged with renal impairment
Time to peak, plasma: 1 to 2 hours
Excretion: Urine (15% to 20% as unchanged drug)