Tetrahydrozoline is a decongestant used to relieve redness in the eyes caused by minor eye irritations (such as smog, swimming, dust, or smoke). It belongs to a class of drugs known as sympathomimetic amines. It works by temporarily narrowing the blood vessels in the eye.

Some brands of tetrahydrozoline eye drops may contain lubricants. Lubricants help protect the eyes from more irritation and dryness.

Use this medication in the affected eye(s) as directed by your doctor, usually up to 4 times a day as needed.

Follow all directions on the product package, or use as directed by your doctor. If you have any questions, ask your doctor or pharmacist.

To apply eye drops, wash your hands first. To avoid contamination, do not touch the dropper tip or let it touch your eye or any other surface. Remove contact lenses before applying the eye drops. Wait at least 10 minutes after using this medication before inserting contact lenses.

Before using, check this product for cloudiness or discoloration. If either is present, do not use the liquid.

Tilt your head back, look upward, and pull down the lower eyelid to make a pouch. Hold the dropper directly over the eye and place 1 drop into the pouch. Look downward and gently close your eyes for 1 to 2 minutes. Place one finger at the corner of the eye near the nose and apply gentle pressure. This will prevent the medication from draining away from the eye. Try not to blink and do not rub the eye. Repeat these steps if your dose is for more than 1 drop and for the other eye if so directed.

Do not rinse the dropper. Replace the dropper cap tightly after each use. If you are using another kind of eye medication (such as drops or ointments), wait at least 5 minutes before applying other medications. Use eye drops before eye ointments to allow the eye drops to enter the eye.

Wait several minutes for your vision to clear before driving or operating machinery.

Overuse of this type of medication may result in increased eye redness (rebound effect when drug wears off). If this occurs, tell your doctor. Do not use this medication for longer than 3 to 4 days at a time.

If your condition lasts or gets worse after 72 hours, or if you think you may have a serious medical problem, stop using this medication and get medical help right away.

Stinging/redness in the eye, widened pupils, or blurred vision may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

If your doctor has directed you to use this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• eye pain
• worsening redness/itching/swelling in or around the eyes
• other vision problems
• shakiness (tremor)
• fast/pounding/ irregular heartbeat
• headache
• sweating
• weakness
• nervousness

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before using tetrahydrozoline, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients (such as preservatives like benzalkonium chloride), which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• glaucoma
• heart problems (such as heart attack, chest pain)
• high blood pressure
• diabetes
• eye infection/injury
• overactive thyroid (hyperthyroidism)

After you apply this drug, your vision may become temporarily blurred. Do not drive, use machinery, or do anything that needs clear vision until you can do it safely.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

This medicine may be harmful if swallowed. If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669. Symptoms of overdose may include drowsiness, severe sweating, decreased body temperature, slow/shallow breathing.

If your symptoms are due to allergies, avoid allergens that may be the cause of your symptoms. Some common causes of allergies include pollen, grasses, weeds, dust mites, and pet dander.

If your doctor has directed you to use this medication on a regular schedule and you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Use your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.