Timolol Maleate 20mg Tablets
WARNING: Do not stop taking this drug all of a sudden. If you do, chest pain that is worse and in some cases heart attack may occur. The risk may be greater if you have certain types of heart disease. To avoid side effects, you will want to slowly stop this drug as ordered by your doctor. Call your doctor right away if you have new or worse chest pain or if other heart problems occur. @ COMMON USES: It is used to treat high blood pressure.It is used after a heart attack to help prevent future heart attacks and lengthen life.It is used to prevent migraine headaches.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antihypertensive, Antianginal, Antimigraine, Post-myocardial Infarction Prophylaxis
Pharmacologic Class
Non-selective Beta-Adrenergic Blocker
Pregnancy Category
Category C
FDA Approved
May 1978
DEA Schedule
Not Controlled
Overview
What is this medicine?
Timolol Maleate is a type of medicine called a beta-blocker. It works by relaxing blood vessels and slowing your heart rate, which helps to lower high blood pressure, prevent chest pain (angina), and reduce the frequency of migraine headaches. It can also be used after a heart attack to improve survival.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Continue taking the medication as directed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store the medication at room temperature, away from light and moisture. Keep it in a dry place, avoiding storage in a bathroom. Ensure that all medications are kept in a safe location, out of reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of medications, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Continue taking the medication as directed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store the medication at room temperature, away from light and moisture. Keep it in a dry place, avoiding storage in a bathroom. Ensure that all medications are kept in a safe location, out of reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of medications, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Do not stop taking this medication suddenly without consulting your doctor, as it can worsen your condition.
- Take your pulse regularly as instructed by your doctor and report if it is too slow.
- Avoid activities requiring mental alertness until you know how the medication affects you, as it can cause dizziness or lightheadedness.
- If you have diabetes, monitor your blood sugar closely, as this medication can mask symptoms of low blood sugar.
- Inform your doctor or dentist that you are taking timolol before any surgery or dental procedures.
- Maintain a healthy diet, exercise regularly, and limit sodium intake as advised by your doctor to help manage blood pressure.
Available Forms & Alternatives
Available Strengths:
- Timolol Maleate 10mg Tablets
- Timolol Maleate 20mg Tablets
- Timolol Maleate 0.25% Opht Sol 5ml
- Timolol Maleate 0.25% Opht Sol 10ml
- Timolol Maleate 0.25% Opht Sol 15ml
- Timolol Maleate 0.5% Ophth Soln 5ml
- Timolol Maleate 0.5% Ophth Sol 10ml
- Timolol Maleate 0.5% Ophth Sol 15ml
- Timolol Maleate 5mg Tablets
- Timolol 0.25% GF Ophth Soln 5ml
- Timolol 0.5% GF Opth Soln 5ml
- Timolol Mal 0.5% Op Sol-Once Daily
- Timolol Mal 0.5% Op Sol-Once Daily
- Timolol Mal 0.5% Ophth Sol 60s
- Timolol 0.25% Pf-Oph Sol 60's
- Timolol Hemi 0.5% Ophth Soln 5ml
- Timolol Hemi 0.5% Ophth Soln 10ml
- Timolol Hemi 0.5% Ophth Soln 15ml
Dosing & Administration
Adult Dosing
Standard Dose:
Hypertension: 20 mg once daily or 10 mg twice daily. Angina: 15-45 mg/day in 2-3 divided doses. Migraine Prophylaxis: 20-30 mg/day in 1-2 divided doses. Post-MI: 10 mg twice daily.
Dose Range:
5 - 60 mg
Condition-Specific Dosing:
Hypertension:
Initial: 10 mg twice daily or 20 mg once daily. Maintenance: 10-60 mg/day in 1-2 doses.
Angina Pectoris:
Initial: 5 mg twice daily. Maintenance: 15-45 mg/day in 2-3 divided doses.
Migraine Prophylaxis:
Initial: 10 mg twice daily. Maintenance: 20-30 mg/day in 1-2 divided doses.
Post-Myocardial Infarction:
10 mg twice daily.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed.
Moderate:
No specific adjustment needed, but monitor for increased effects.
Severe:
Use with caution. Consider dose reduction and monitor for accumulation (e.g., if CrCl < 15 mL/min).
Dialysis:
Timolol is not significantly removed by hemodialysis. Monitor for increased effects.
Hepatic Impairment:
Mild:
Use with caution. Monitor for increased effects.
Moderate:
Consider dose reduction (e.g., 50% of usual dose) and monitor closely due to reduced first-pass metabolism.
Severe:
Significant dose reduction likely required. Monitor closely for adverse effects.
Pharmacology
Mechanism of Action
Timolol is a non-selective beta-adrenergic receptor blocking agent. It competitively blocks both beta-1 and beta-2 adrenergic receptors. This results in decreased heart rate, decreased myocardial contractility, decreased cardiac output, and reduced blood pressure. It also inhibits renin release from the kidneys. In migraine prophylaxis, its mechanism is not fully understood but may involve modulation of central adrenergic activity or vascular effects.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 50%
Tmax:
1-2 hours
FoodEffect:
Food may slightly increase the rate and extent of absorption, but it is not clinically significant.
Distribution:
Vd:
Approximately 1.7 L/kg
ProteinBinding:
Approximately 10%
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 4-5 hours
Clearance:
Not readily available (highly variable due to first-pass metabolism)
ExcretionRoute:
Renal (primarily as metabolites, some unchanged drug)
Unchanged:
Approximately 20% (renal excretion)
Pharmacodynamics
OnsetOfAction:
Within 30 minutes (antihypertensive effect)
PeakEffect:
1-2 hours (antihypertensive effect)
DurationOfAction:
12-24 hours (antihypertensive effect)
Safety & Warnings
BLACK BOX WARNING
Abrupt Cessation of Therapy: Exacerbation of angina pectoris, and in some cases, myocardial infarction and ventricular arrhythmia have occurred following abrupt discontinuation of therapy with beta-blockers. When discontinuing chronically administered timolol maleate, particularly in patients with ischemic heart disease, the dosage should be gradually reduced over a period of 1 to 2 weeks and the patient should be carefully monitored. If angina worsens or acute coronary insufficiency develops, timolol maleate administration should be reinstituted promptly, at least temporarily, and other measures appropriate for the management of unstable angina pectoris should be taken. Patients should be warned against interruption or discontinuation of therapy without the physician's advice. Because coronary artery disease is common and may be unrecognized, it may be prudent to discontinue timolol maleate therapy slowly even in patients treated only for hypertension.
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Shortness of breath, sudden weight gain, or swelling in the arms or legs
Chest pain or pressure
Abnormally slow heartbeat
Irregular heartbeat
Muscle weakness
Changes in vision
Feeling cold
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness
Fatigue
Weakness
* Upset stomach
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Shortness of breath, sudden weight gain, or swelling in the arms or legs
Chest pain or pressure
Abnormally slow heartbeat
Irregular heartbeat
Muscle weakness
Changes in vision
Feeling cold
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness
Fatigue
Weakness
* Upset stomach
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting
- Very slow heart rate (less than 50 beats per minute)
- Shortness of breath, wheezing, or difficulty breathing (especially if you have asthma or COPD)
- Swelling of ankles or feet
- Unusual weight gain
- New or worsening chest pain
- Symptoms of depression (e.g., persistent sadness, loss of interest)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction and its symptoms.
Certain health conditions, including:
+ Breathing problems, such as asthma or chronic obstructive pulmonary disease (COPD)
+ Heart block or heart failure (weak heart)
+ Shock caused by heart problems
+ Slow heartbeat
This list is not exhaustive, and it is crucial to discuss all your health problems and medications with your doctor.
To ensure your safety, please inform your doctor and pharmacist about:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* All your health problems
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to confirm it is safe to do so.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction and its symptoms.
Certain health conditions, including:
+ Breathing problems, such as asthma or chronic obstructive pulmonary disease (COPD)
+ Heart block or heart failure (weak heart)
+ Shock caused by heart problems
+ Slow heartbeat
This list is not exhaustive, and it is crucial to discuss all your health problems and medications with your doctor.
To ensure your safety, please inform your doctor and pharmacist about:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* All your health problems
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to confirm it is safe to do so.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
To ensure your safety, avoid driving and other activities that require alertness until you understand how this medication affects you. When changing positions, such as standing up from a sitting or lying down position, do so slowly to minimize the risk of dizziness or fainting. Be cautious when using stairs.
As directed by your doctor, regularly have your blood work and other laboratory tests checked. Additionally, monitor your blood pressure and heart rate as instructed by your doctor.
Before consuming alcohol, discuss its potential effects with your doctor. This medication may mask certain symptoms of low blood sugar, such as a rapid heartbeat, which can increase the risk of severe or prolonged low blood sugar episodes. This risk is particularly higher in individuals with diabetes, children, and those who are fasting, undergoing surgery, have a reduced appetite, or are experiencing vomiting. If you have concerns, consult your doctor.
If you have diabetes, it is crucial to closely monitor your blood sugar levels. If you are taking this medication and have high blood pressure, consult your doctor before using over-the-counter (OTC) products that may increase blood pressure, such as cough or cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
This medication may make it more challenging to recognize symptoms of an overactive thyroid, such as a rapid heartbeat. If you have an overactive thyroid and suddenly stop taking this medication, your condition may worsen and become life-threatening. Discuss this with your doctor.
If you have a history of severe allergic reactions, inform your doctor, as you may be at a higher risk of an even more severe reaction if you are exposed to the allergen again. If you use epinephrine to treat severe allergic reactions, consult your doctor, as this medication may reduce the effectiveness of epinephrine.
If you are pregnant, plan to become pregnant, or are breastfeeding, inform your doctor to discuss the potential benefits and risks to you and your baby.
To ensure your safety, avoid driving and other activities that require alertness until you understand how this medication affects you. When changing positions, such as standing up from a sitting or lying down position, do so slowly to minimize the risk of dizziness or fainting. Be cautious when using stairs.
As directed by your doctor, regularly have your blood work and other laboratory tests checked. Additionally, monitor your blood pressure and heart rate as instructed by your doctor.
Before consuming alcohol, discuss its potential effects with your doctor. This medication may mask certain symptoms of low blood sugar, such as a rapid heartbeat, which can increase the risk of severe or prolonged low blood sugar episodes. This risk is particularly higher in individuals with diabetes, children, and those who are fasting, undergoing surgery, have a reduced appetite, or are experiencing vomiting. If you have concerns, consult your doctor.
If you have diabetes, it is crucial to closely monitor your blood sugar levels. If you are taking this medication and have high blood pressure, consult your doctor before using over-the-counter (OTC) products that may increase blood pressure, such as cough or cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
This medication may make it more challenging to recognize symptoms of an overactive thyroid, such as a rapid heartbeat. If you have an overactive thyroid and suddenly stop taking this medication, your condition may worsen and become life-threatening. Discuss this with your doctor.
If you have a history of severe allergic reactions, inform your doctor, as you may be at a higher risk of an even more severe reaction if you are exposed to the allergen again. If you use epinephrine to treat severe allergic reactions, consult your doctor, as this medication may reduce the effectiveness of epinephrine.
If you are pregnant, plan to become pregnant, or are breastfeeding, inform your doctor to discuss the potential benefits and risks to you and your baby.
Overdose Information
Overdose Symptoms:
- Severe bradycardia (slow heart rate)
- Hypotension (low blood pressure)
- Bronchospasm
- Acute cardiac failure
- Cardiogenic shock
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222.
Drug Interactions
Contraindicated Interactions
- Non-dihydropyridine calcium channel blockers (e.g., verapamil, diltiazem) administered intravenously (risk of severe bradycardia, heart block, heart failure)
- MAO inhibitors (within 14 days of use)
Major Interactions
- Other beta-blockers (additive effects, severe bradycardia, hypotension)
- Clonidine (risk of rebound hypertension upon clonidine withdrawal if beta-blocker is not tapered first)
- Digoxin (additive bradycardia)
- Insulin and oral hypoglycemics (masking of hypoglycemia symptoms, prolonged hypoglycemia)
- NSAIDs (e.g., ibuprofen, naproxen) (may reduce antihypertensive effect of beta-blockers)
- CYP2D6 inhibitors (e.g., fluoxetine, paroxetine, quinidine) (increase timolol plasma concentrations)
- Sympathomimetics (e.g., epinephrine, norepinephrine) (unopposed alpha-adrenergic stimulation, leading to severe hypertension and bradycardia)
Moderate Interactions
- Alpha-1 blockers (e.g., prazosin, doxazosin) (risk of orthostatic hypotension)
- Other antihypertensives (additive hypotensive effects)
- Class I antiarrhythmics (e.g., disopyramide, flecainide) (additive negative inotropic and dromotropic effects)
- General anesthetics (additive myocardial depression, hypotension)
Minor Interactions
- Alcohol (may enhance hypotensive effect)
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing.
Timing: Prior to initiation
Heart Rate (HR)
Rationale: To establish baseline and assess for bradycardia.
Timing: Prior to initiation
Electrocardiogram (ECG)
Rationale: To assess for pre-existing conduction abnormalities.
Timing: Prior to initiation (especially in patients with cardiac history)
Pulmonary Function Tests (PFTs)
Rationale: To assess for underlying obstructive airway disease (e.g., asthma, COPD) due to non-selective beta-blockade.
Timing: Prior to initiation in patients with respiratory symptoms or history
Blood Glucose
Rationale: For diabetic patients, as beta-blockers can mask hypoglycemia symptoms.
Timing: Prior to initiation
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly (e.g., weekly during dose titration, then monthly or quarterly)
Target: <130/80 mmHg (or individualized target)
Action Threshold: Hypotension (e.g., SBP <90 mmHg or symptomatic), or uncontrolled hypertension
Heart Rate (HR)
Frequency: Regularly (e.g., weekly during dose titration, then monthly or quarterly)
Target: 50-60 bpm (resting)
Action Threshold: Bradycardia (<50 bpm or symptomatic), or heart block
Blood Glucose
Frequency: More frequently in diabetic patients (e.g., daily self-monitoring)
Target: Individualized
Action Threshold: Frequent or severe hypoglycemia
Respiratory Status
Frequency: Regularly, especially in patients with respiratory conditions
Target: Normal breathing, no wheezing or dyspnea
Action Threshold: Worsening asthma/COPD symptoms, bronchospasm
Symptom Monitoring
- Dizziness
- Lightheadedness
- Fatigue
- Bradycardia (slow pulse)
- Dyspnea (shortness of breath)
- Wheezing
- Cold extremities
- Depression
- Insomnia
- Masked symptoms of hypoglycemia (in diabetics)
Special Patient Groups
Pregnancy
Category C. Use only if the potential benefit justifies the potential risk to the fetus. Beta-blockers can cause fetal bradycardia, hypoglycemia, and growth restriction. Neonates exposed to beta-blockers in utero may be at risk for hypoglycemia and bradycardia.
Trimester-Specific Risks:
First Trimester:
Limited data, but generally considered low risk for major malformations.
Second Trimester:
Potential for fetal bradycardia, growth restriction, and reduced placental perfusion.
Third Trimester:
Increased risk of neonatal bradycardia, hypoglycemia, and respiratory depression at birth. Monitor neonate for several days post-delivery.
Lactation
Timolol is excreted into breast milk. The American Academy of Pediatrics considers it compatible with breastfeeding, but caution is advised. Monitor the infant for signs of beta-blockade (e.g., bradycardia, lethargy, hypoglycemia).
Infant Risk:
Low to moderate risk (L3). Potential for bradycardia, hypoglycemia, and respiratory depression in the infant, especially with higher maternal doses or in premature infants.
Pediatric Use
Safety and effectiveness in pediatric patients have not been established for systemic use. Generally not recommended for routine use in children for hypertension or angina.
Geriatric Use
Use with caution. Elderly patients may be more sensitive to the effects of beta-blockers, particularly regarding bradycardia and hypotension. Start with lower doses and titrate slowly. Monitor renal and hepatic function.
Clinical Information
Clinical Pearls
- Timolol is a non-selective beta-blocker, meaning it blocks both beta-1 (cardiac) and beta-2 (pulmonary, vascular) receptors. This necessitates caution in patients with asthma, COPD, or peripheral vascular disease due to potential for bronchospasm or worsening claudication.
- Abrupt discontinuation can lead to rebound hypertension, angina exacerbation, or myocardial infarction, especially in patients with underlying coronary artery disease. Taper dose gradually over 1-2 weeks.
- Can mask symptoms of hypoglycemia (e.g., tremor, palpitations) in diabetic patients, making it harder to recognize and treat low blood sugar.
- May cause fatigue, dizziness, or depression. Advise patients to report these symptoms.
- Often used as a first-line agent for migraine prophylaxis due to its efficacy and once-daily dosing potential.
Alternative Therapies
- Other beta-blockers (e.g., metoprolol, atenolol, propranolol, carvedilol)
- ACE inhibitors (e.g., lisinopril, enalapril)
- Angiotensin Receptor Blockers (ARBs) (e.g., losartan, valsartan)
- Calcium Channel Blockers (e.g., amlodipine, nifedipine, diltiazem, verapamil)
- Diuretics (e.g., hydrochlorothiazide, furosemide)
- Alpha-blockers (e.g., prazosin, doxazosin)
- Central alpha-agonists (e.g., clonidine)
Cost & Coverage
Average Cost:
$10 - $30 per 30 tablets (generic 20mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 (Generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more details. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide information about the medication taken, the amount, and the time it happened.