Timolol Side Effects: 5 Things to Watch for With This Beta Blocker Eye Drop

Glaucoma refers to a group of eye conditions affecting your optic nerve (the nerve at the back of each eye that allows you to see). Without treatment, glaucoma can cause vision loss and even blindness. Fortunately, numerous medications are available to treat this condition. 

Eye drops, such as timolol (Betimol, Timoptic, Timoptic XE), are often prescribed for glaucoma. Timolol is also approved to treat increased pressure in the eye from other causes. It works by decreasing how much fluid your eyes make. Although timolol is typically well tolerated, it has a few risks as well. Below, we discuss timolol side effects and what you can do to prevent or manage them.

Timolol is a beta blocker that’s also available as an oral medication, but it’s not as commonly used as other oral beta blockers. So in this article, we’ll focus on timolol eye drops only.

Promotion disclosure

Timolol

Avg retail price

$15.69(Save 51.56%)

GoodRx discount

$7.60

See all discounts

How it works

Use GoodRx to find medications, pharmacies, and discounts.

GoodRx discounts can help you pay less for your prescription.

Bring your free coupon or savings card to the pharmacy.

Timolol side effects at a glance

Below we’ll discuss typically mild timolol side effects. We’ll also list more severe (but rare) side effects that can occur. But keep in mind that this isn’t a full list of possible risks.

Mild side effects that occur in the eye include:

• Burning

• Stinging

• Pain

• Dryness

• Itchiness

• Redness

• Inflammation

• Crusting

• Tearing up

• Feeling that something is in your eye

• Vision changes

Non-eye related side effects can also occur, such as:

• Respiratory infections

• Headache

• Dizziness

• Nausea

• Dry mouth

Rare but serious side effects may include:

• Heart problems

• Masking symptoms of low blood glucose (hypoglycemia) or overactive thyroid (hyperthyroidism)

• New or worsened heart failure

• Worsening asthma or other lung condition symptoms

• Eye infections if eye drops become contaminated

• Low blood pressure (hypotension)

• Muscle weakness, including worsening symptoms of myasthenia gravis

EXPERT PICKS: WHAT TO READ NEXT

• What is glaucoma? Learn about what symptoms to watch for and how glaucoma is treated.

• How is glaucoma treated? Glaucoma is often treated with eye drops, but there are several different options.

• How do you prevent glaucoma from getting worse? Learn some tips for preventing glaucoma from causing permanent eye damage, including vision loss.

Let’s take a closer look at five timolol side effects and what to do if you experience them.

1. Eye irritation

A wide range of eye-related problems can occur with timolol, though they’re often mild. This may include burning, stinging, and pain. Thankfully, these sensations are usually temporary and should go away on their own soon after administering the eye drops.

However, if you have eye pain or irritation that doesn’t go away while using timolol eye drops, contact your prescriber. They’ll likely want to see you in person in order to determine possible causes for your symptoms.

2. Eye inflammation and infection

While eye crusting, dryness, and inflammation can be mild side effects of timolol, sometimes these are a sign of an inflammatory or infectious eye-related condition. Examples include blepharitis (inflammation of the eyelid), keratitis (inflammation of the cornea), and conjunctivitis (inflammation or infection of the lining inside the eyelid).

Symptoms of these eye conditions may include:

• Crusting

• Excessive tearing

• Eye discharge

• Blurry vision

• Swelling

• Redness

• Itching

But keep in mind that some of these symptoms, such as itching, may also just be a mild side effect of timolol. And you may be able to manage them at home. However, if you're experiencing any of these, especially if they feel severe or don’t go away soon after using timolol, contact your prescriber. You may need medications to treat the condition, including antibiotics. Untreated infections can lead to vision problems. 

To help prevent inflammation and infection from timolol, take steps to avoid contaminating your timolol bottle. Don’t let the tip of the bottle touch your fingers or other surfaces. And don’t touch your eye with the tip of the bottle.

3. Headache

Timolol eye drops can cause headaches. While it’s not extremely common, it can happen.

There are several causes for headaches, so it can be hard to tell if timolol is the culprit or if there’s another cause. Tracking your headaches can help you determine the cause in some cases. Try to pay attention to when you experience headaches, and if they occur after using timolol eye drops.

If you’re experiencing headaches after starting timolol, talk to your prescriber. They may provide some tips to minimize headaches, such as doing breathing exercises, making certain dietary changes, or improving your sleep habits.

Over-the-counter pain relievers, such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin), may also be an option. Check with your prescriber first, though. Although these medications aren’t known to interact with timolol, they aren’t safe for everyone.

Additionally, overusing timolol can raise your risk for headaches. Carefully follow the dosage instructions from your prescriber.

4. Dizziness

Dizziness is a common side effect of oral beta blockers. Although timolol eye drops aren’t as fully absorbed by the body as oral medications, they do still enter the bloodstream. Therefore, dizziness is a possible side effect, though it’s less common than it is with oral beta blockers. However, dizziness is more likely if you use too much of the timolol eye drops or use it too frequently. As with headaches, you can lower your risk for dizziness by carefully following dosage instructions from your prescriber.

If you experience dizziness with timolol that doesn’t improve quickly, reach out to your prescriber. Your dizziness may be caused by something else, and they may want to evaluate you further.

5. Worsening of chronic conditions

One possible risk of timolol eye drops is that it can worsen heart, lung, or muscle-related conditions. This includes:

• Uncontrolled heart failure

• Myasthenia gravis

• Chronic obstructive pulmonary disease (COPD)

• Asthma

As discussed, timolol eye drops work in the eye but they do get absorbed by the body. The amount absorbed won’t cause problems for most people. But if you have certain health conditions, you may be at greater risk of side effects.

Your prescriber may recommend avoiding timolol eye drops if you have these conditions. So make sure they have your full health history before starting this medication. They can let you know if they think it’s too risky. Or they may just ask you to monitor for signs and symptoms that your health condition is worsening.

Why trust our experts?

Written by:

Alex Brewer, PharmD, MBA

Alex Brewer, PharmD, MBA, is a licensed pharmacist specializing in chronic disease and health and wellness. Upon completing his residency, he worked in the managed care field, conducting medication therapy management and adherence counseling sessions with Medicaid, Medicare, and private insurance patients, before transitioning to a career in medical writing.

Edited by:

Amy B. Gragnolati, PharmD, BCPS

Amy Gragnolati, PharmD, BCPS, is a pharmacy editor for GoodRx. Amy currently holds her pharmacist license in Georgia and California.

Reviewed by:

Austin Ulrich, PharmD, BCACP

Austin Ulrich, PharmD, BCACP, is a board-certified ambulatory care clinical pharmacist. In his early career, he provided direct patient care in a variety of settings, including hospital and community pharmacies, and in a primary care clinic as a clinical pharmacist.

Our editorial standards

Meet our experts