Timolol (Systemic)

• If you have an allergy to timolol or any other part of timolol.
• If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
• If you have any of these health problems: Asthma or other breathing problems like COPD (chronic obstructive pulmonary disease).
• If you have any of these health problems: Heart block, shock caused by heart problems, or slow heartbeat.
• If you have heart failure (weak heart).
• If you are breast-feeding or plan to breast-feed.

This is not a list of all drugs or health problems that interact with this medicine.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take timolol with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Dizziness.
• Feeling tired or weak.
• Upset stomach.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

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

Absorption

Rapid and complete (~90%)

Distribution

Vd: 1.7 L/kg

Metabolism

Extensively hepatic via CYP2D6; extensive first-pass effect

Excretion

Urine (15% to 20% as unchanged drug)

Treatment of hypertension and angina; to reduce mortality following myocardial infarction; prophylaxis of migraine

The 2014 guideline for the management of high blood pressure in adults (JNC 8) recommends initiation of pharmacologic treatment to lower blood pressure for the following patients (JNC8 [James, 2013]):

• Patients ≥60 years of age, with systolic blood pressure (SBP) ≥150 mm Hg or diastolic blood pressure (DBP) ≥90 mm Hg. Goal of therapy is SBP <150 mm Hg and DBP <90 mm Hg.

• Patients <60 years of age, with SBP ≥140 mm Hg or DBP ≥90 mm Hg. Goal of therapy is SBP <140 mm Hg and DBP <90 mm Hg.

• Patients ≥18 years of age with diabetes, with SBP ≥140 mm Hg or DBP ≥90 mm Hg. Goal of therapy is SBP <140 mm Hg and DBP <90 mm Hg.

• Patients ≥18 years of age with chronic kidney disease (CKD), with SBP ≥140 mm Hg or DBP ≥90 mm Hg. Goal of therapy is SBP <140 mm Hg and DBP <90 mm Hg.

In patients with chronic kidney disease (CKD), regardless of race or diabetes status, the use of an ACE inhibitor (ACEI) or angiotensin receptor blocker (ARB) as initial therapy is recommended to improve kidney outcomes. In the general nonblack population (without CKD) including those with diabetes, initial antihypertensive treatment should consist of a thiazide-type diuretic, calcium channel blocker, ACEI, or ARB. In the general black population (without CKD) including those with diabetes, initial antihypertensive treatment should consist of a thiazide-type diuretic or a calcium channel blocker instead of an ACEI or ARB.

Refer to adult dosing.

There are no specific dosage adjustments provided in manufacturer’s labeling. However, timolol is partially metabolized by the liver; dosage reduction may be necessary.

Should be administered with food at the same time each day.

Abiraterone Acetate: May increase the serum concentration of CYP2D6 Substrates. Management: Avoid concurrent use of abiraterone with CYP2D6 substrates that have a narrow therapeutic index whenever possible. When concurrent use is not avoidable, monitor patients closely for signs/symptoms of toxicity. Consider therapy modification

Acetylcholinesterase Inhibitors: May enhance the bradycardic effect of Beta-Blockers. Monitor therapy

Ajmaline: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy

Alfuzosin: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Alpha-/Beta-Agonists (Direct-Acting): Beta-Blockers may enhance the vasopressor effect of Alpha-/Beta-Agonists (Direct-Acting). Epinephrine used as a local anesthetic for dental procedures will not likely cause clinically relevant problems. Some beta-adrenoceptor mediated effects of Alpha-/Beta-Agonists (Direct-Acting), including anti-anaphylactic effects of epinephrine, may be diminished by Beta-Blockers. Management: Cardioselective beta-blockers and lower doses of epinephrine may confer a more limited risk. Patients who may require acute subcutaneous epinephrine (e.g., bee sting kits) should probably avoid beta blockers. Exceptions: Dipivefrin. Consider therapy modification

Alpha1-Blockers: Beta-Blockers may enhance the orthostatic hypotensive effect of Alpha1-Blockers. The risk associated with ophthalmic products is probably less than systemic products. Monitor therapy

Alpha2-Agonists: May enhance the AV-blocking effect of Beta-Blockers. Sinus node dysfunction may also be enhanced. Beta-Blockers may enhance the rebound hypertensive effect of Alpha2-Agonists. This effect can occur when the Alpha2-Agonist is abruptly withdrawn. 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. Exceptions: Apraclonidine. Consider therapy modification

Amifostine: Blood Pressure Lowering Agents may enhance the hypotensive effect of Amifostine. Management: When amifostine is used at chemotherapy doses, blood pressure lowering medications should be withheld for 24 hours prior to amifostine administration. If blood pressure lowering therapy cannot be withheld, amifostine should not be administered. Consider therapy modification

Aminoquinolines (Antimalarial): May decrease the metabolism of Beta-Blockers. Monitor therapy

Amiodarone: May enhance the bradycardic effect of Beta-Blockers. Possibly to the point of cardiac arrest. Amiodarone may increase the serum concentration of Beta-Blockers. Monitor therapy

Amphetamines: May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy

Anilidopiperidine Opioids: May enhance the bradycardic effect of Beta-Blockers. Anilidopiperidine Opioids may enhance the hypotensive effect of Beta-Blockers. Monitor therapy

Antipsychotic Agents (Phenothiazines): May enhance the hypotensive effect of Beta-Blockers. Beta-Blockers may decrease the metabolism of Antipsychotic Agents (Phenothiazines). Antipsychotic Agents (Phenothiazines) may decrease the metabolism of Beta-Blockers. Monitor therapy

Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may enhance the hypotensive effect of Antipsychotic Agents (Second Generation [Atypical]). Monitor therapy

Asunaprevir: May increase the serum concentration of CYP2D6 Substrates. Consider therapy modification

Barbiturates: May decrease the serum concentration of Beta-Blockers. Monitor therapy

Barbiturates: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Benperidol: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Beta2-Agonists: Beta-Blockers (Nonselective) may diminish the bronchodilatory effect of Beta2-Agonists. Avoid combination

Bradycardia-Causing Agents: May enhance the bradycardic effect of other Bradycardia-Causing Agents. Monitor therapy

Bretylium: May enhance the bradycardic effect of Bradycardia-Causing Agents. Bretylium may also enhance atrioventricular (AV) blockade in patients receiving AV blocking agents. Monitor therapy

Brigatinib: May diminish the antihypertensive effect of Antihypertensive Agents. Brigatinib may enhance the bradycardic effect of Antihypertensive Agents. Monitor therapy

Brimonidine (Topical): May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Bupivacaine: Beta-Blockers may increase the serum concentration of Bupivacaine. Monitor therapy

Calcium Channel Blockers (Nondihydropyridine): May enhance the hypotensive effect of Beta-Blockers. Bradycardia and signs of heart failure have also been reported. Calcium Channel Blockers (Nondihydropyridine) may increase the serum concentration of Beta-Blockers. Exceptions: Bepridil. Monitor therapy

Cardiac Glycosides: Beta-Blockers may enhance the bradycardic effect of Cardiac Glycosides. Monitor therapy

Ceritinib: Bradycardia-Causing Agents may enhance the bradycardic effect 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. Avoid combination

Cholinergic Agonists: Beta-Blockers may enhance the adverse/toxic effect of Cholinergic Agonists. Of particular concern are the potential for cardiac conduction abnormalities and bronchoconstriction. Management: Administer these agents in combination with caution, and monitor for conduction disturbances. Avoid methacholine with any beta blocker due to the potential for additive bronchoconstriction. Monitor therapy

Cobicistat: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy

CYP2D6 Inhibitors (Moderate): May decrease the metabolism of CYP2D6 Substrates. Monitor therapy

CYP2D6 Inhibitors (Strong): May decrease the metabolism of CYP2D6 Substrates. Consider therapy modification

Darunavir: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy

Diazoxide: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Dipyridamole: May enhance the bradycardic effect of Beta-Blockers. Monitor therapy

Disopyramide: May enhance the bradycardic effect of Beta-Blockers. Beta-Blockers may enhance the negative inotropic effect of Disopyramide. Monitor therapy

Dronedarone: May enhance the bradycardic effect of Beta-Blockers. Dronedarone may increase the 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. Consider therapy modification

DULoxetine: Blood Pressure Lowering Agents may enhance the hypotensive effect of DULoxetine. Monitor therapy

Ergot Derivatives: Beta-Blockers may enhance the vasoconstricting effect of Ergot Derivatives. Exceptions: Nicergoline. Consider therapy modification

Fingolimod: Beta-Blockers may enhance the bradycardic effect of Fingolimod. Management: Avoid the concomitant use of fingolimod and beta-blockers if possible. If coadministration is necessary, patients should have overnight continuous ECG monitoring conducted after the first dose of fingolimod. Monitor patients for bradycardia. Consider therapy modification

Floctafenine: May enhance the adverse/toxic effect of Beta-Blockers. Avoid combination

Grass Pollen Allergen Extract (5 Grass Extract): Beta-Blockers may enhance the adverse/toxic effect 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. Consider therapy modification

Herbs (Hypertensive Properties): May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy

Herbs (Hypotensive Properties): May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Hypotension-Associated Agents: Blood Pressure Lowering Agents may enhance the hypotensive effect of Hypotension-Associated Agents. Monitor therapy

Imatinib: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy

Insulin: Beta-Blockers may enhance the hypoglycemic effect of Insulin. Monitor therapy

Ivabradine: Bradycardia-Causing Agents may enhance the bradycardic effect of Ivabradine. Monitor therapy

Lacosamide: Bradycardia-Causing Agents may enhance the AV-blocking effect of Lacosamide. Monitor therapy

Levodopa: Blood Pressure Lowering Agents may enhance the hypotensive effect of Levodopa. Monitor therapy

Lidocaine (Systemic): Beta-Blockers may increase the serum concentration of Lidocaine (Systemic). Monitor therapy

Lidocaine (Topical): Beta-Blockers may increase the serum concentration of Lidocaine (Topical). Monitor therapy

Lormetazepam: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Lumefantrine: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy

Mepivacaine: Beta-Blockers may increase the serum concentration of Mepivacaine. Monitor therapy

Methacholine: Beta-Blockers may enhance the adverse/toxic effect of Methacholine. Avoid combination

Methoxyflurane: May enhance the hypotensive effect of Beta-Blockers. Monitor therapy

Methylphenidate: May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy

Midodrine: Beta-Blockers may enhance the bradycardic effect of Midodrine. Monitor therapy

Molsidomine: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Naftopidil: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Nicergoline: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Nicorandil: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

NIFEdipine: May enhance the hypotensive effect of Beta-Blockers. NIFEdipine may enhance the negative inotropic effect of Beta-Blockers. Monitor therapy

Nitroprusside: Blood Pressure Lowering Agents may enhance the hypotensive effect of Nitroprusside. Monitor therapy

Nonsteroidal Anti-Inflammatory Agents: May diminish the antihypertensive effect of Beta-Blockers. Monitor therapy

Obinutuzumab: May enhance the hypotensive effect 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. Consider therapy modification

Panobinostat: May increase the serum concentration of CYP2D6 Substrates. Management: Avoid concurrent use of sensitive CYP2D6 substrates when possible, particularly those substrates with a narrow therapeutic index. Consider therapy modification

Peginterferon Alfa-2b: May decrease the serum concentration of CYP2D6 Substrates. Peginterferon Alfa-2b may increase the serum concentration of CYP2D6 Substrates. Monitor therapy

Pentoxifylline: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Perhexiline: CYP2D6 Substrates may increase the serum concentration of Perhexiline. Perhexiline may increase the serum concentration of CYP2D6 Substrates. Monitor therapy

Pholcodine: Blood Pressure Lowering Agents may enhance the hypotensive effect of Pholcodine. Monitor therapy

Phosphodiesterase 5 Inhibitors: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Propafenone: May increase the serum concentration of Beta-Blockers. Propafenone possesses some independent beta blocking activity. Monitor therapy

Prostacyclin Analogues: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

Quinagolide: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy

QuiNINE: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy

Regorafenib: May enhance the bradycardic effect of Beta-Blockers. Monitor therapy

Reserpine: May enhance the hypotensive effect of Beta-Blockers. Monitor therapy

Rifamycin Derivatives: May decrease the serum concentration of Beta-Blockers. Exceptions: Rifabutin. Monitor therapy

Rivastigmine: May enhance the bradycardic effect of Beta-Blockers. Avoid combination

Ruxolitinib: May enhance the bradycardic effect of Bradycardia-Causing Agents. Management: Ruxolitinib Canadian product labeling recommends avoiding use with bradycardia-causing agents to the extent possible. Monitor therapy

Selective Serotonin Reuptake Inhibitors: May increase the serum concentration of Beta-Blockers. Exceptions: Citalopram; Escitalopram; FluvoxaMINE. Monitor therapy

Sulfonylureas: Beta-Blockers may enhance the hypoglycemic effect of Sulfonylureas. Cardioselective beta-blockers (eg, acebutolol, atenolol, metoprolol, and penbutolol) may be safer than nonselective beta-blockers. All beta-blockers appear to mask tachycardia as an initial symptom of hypoglycemia. Ophthalmic beta-blockers are probably associated with lower risk than systemic agents. Monitor therapy

Theophylline Derivatives: Beta-Blockers (Nonselective) may diminish the bronchodilatory effect of Theophylline Derivatives. Consider therapy modification

Tofacitinib: May enhance the bradycardic effect of Bradycardia-Causing Agents. Monitor therapy

Yohimbine: May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy