If you’re considering getting contact lenses, there are a few things you need to know. This guide is for anyone interested in contact lenses, especially if you:
Are getting your first vision correction treatment
Are interested in contacts for cosmetic reasons
Your eye health is a vital aspect of your overall health. It’s crucial to make an informed decision when deciding which contacts to buy. That’s why we put together this guide. We’ll answer common questions and help you find comfortable, healthy, and clear vision.
*This guide is not intended to replace the advice of an eye doctor. You should rely on a qualified eye care professional for personalized information and recommendations.
1. Schedule a Contact Lens Fitting
The most important thing to know is that you’ll need an eye examination and contact lens fitting. This can be performed by an eye doctor (optometrist or ophthalmologist).
During the eye exam, your doctor will check the overall health of your eye. They will determine your eye prescription, test how your eyes work together, check the fluid pressure in your eyes, and check to see if you have any eye infections or conditions.
An eye exam is not enough to determine your contact lens prescription. Your eye doctor will need to perform a contact lens exam for this. They may measure:
Your corneal curvature
Pupil or iris size
Tear film quality
These measurements will help your eye doctor determine whether you should wear contact lenses or not. They will also discuss your lifestyle to help you determine a healthy wear and replacement schedule. Many eye doctors will then give you a free trial pair of contacts to test out for a week or two.
Your eye doctor’s recommendations are the best source of information for which type and brand of contact lens or other eyewear you should purchase.
Contact lens and glasses prescriptions are different. Glasses rest about 12mm from your eyes, whereas contacts are placed directly on your eyes. This means that the strengths of the prescription may be different.
Example of a Contact Lens Prescription
Example of an Eyeglasses Prescription
The two types of prescriptions contain some of the same information. Though these may refer to the same prescription elements, the numbers may be different depending on the device.
For both prescriptions, OD stands for oculus dexter, and means right eye. OS stands for oculus sinister, and means left eye.
POWER (PWR) or SPHERE (SPH) is shown on both types of prescription. This is the refractive power (commonly called “strength”) of your prescription. (+) indicates farsightedness correction and (-) indicates nearsightedness correction. The larger the number, the stronger the prescription.
Cylinder (CYL) and AXIS are measurements for people with astigmatism. CYL measures the amount of astigmatism correction. AXIS measures the direction of astigmatism correction. They appear on both prescriptions but will only have a number if the patient has astigmatism.
B.C. stands for base curve and measures the curvature of the inside of a contact lens. The number is usually between 8 and 10. This should match the curvature of your eye to achieve maximum comfort and fit.
DIA represents the diameter of the lens, or width from edge to edge. This number is usually between 13 and 15 mm (smaller for rigid gas-permeable lenses). It determines where the contact sits on your eye.
You’ll receive separate prescriptions for your eyeglasses and contact lenses. Be sure to ask your eye doctor for a copy of each. Especially if you’re planning on purchasing contacts or glasses online.
3. Types of Contacts
There are two types of contact lenses:
Hard (rigid gas-permeable, or RGP)
Soft contacts
Rigid gas-permeable contact lenses are not as popular as soft lenses, though some people still prefer them. They are custom-shaped to the patient’s eye shape, which may provide you with sharper vision. They are more durable and last longer (typically 1-2 years). RGP lenses move on your eye with each blink, allowing oxygen and tears under the lens.
Soft contact lenses are much more common than RGP lenses. Most people find the silicone hydrogel material of soft lenses more comfortable. There are a wide variety of soft lenses available. Each type of soft lens will have a specific wear and replacement schedule, so you can find one that fits your needs and lifestyle.
Toric lensesare a special type of contacts for people with astigmatism. They have a slightly different shape to take the misshapen cornea into account.
Multifocal contact lenses are available for people with presbyopia. They can replace bifocal or multifocal eyeglasses.
4. Wear & Replacement Schedules
Soft contact lenses all come with recommended patient wear routines. These, combined with your eye doctor’s personalized directions, will make up your wear and replacement schedule.
There are three standard types of soft lenses:
Daily disposable lenses are worn for one day and then discarded. They are rising in popularity due to their convenience and safety. With dailies, you don’t need a contact case or solution.
You simply throw them away at the end of the day. Weekly or monthly lenses are susceptible to the build-up of proteins and lipids, which can cause eye infections. Daily lenses negate the risk of build-up. They are also very popular with people with dry eyes.
Weekly/bi-weekly lenses get replaced every week or two, depending on your eyes. They offer a balance of convenience and comfort. The popular Acuvue Oasys lenses are an example of bi-weekly lenses.
Monthly contact lensesneed to be replaced 30 days after opening. They are the most cost-effective type of soft lenses. However, they do require more cleaning and maintenance than daily disposables.
Extended wear contacts are FDA approved for overnight wear. Most are approved for seven days and six nights. While Air Optix Night & Day lenses are approved for 30 days and nights of continuous wear.
*Important Safety Information: Not all patients can wear the lenses for extended wear. Approximately 80% of patients are able to wear the contacts during the day and at night. Always follow the eye care professional’s recommended lens wear, care and replacement schedule. Overnight wear of contact lenses has been shown to increase the risk of certain serious contact lens–related complications.
5. Buying Contacts Online
Buying contacts online is simple, safe, and convenient (and often cheaper) as long as you’ve had a professional contact lens fitting beforehand.
If you have never worn contacts, you should see an eye doctor. They will perform an eye exam and fitting and give you pointers and help you put your contacts in for the first time.
However, once you know what brand of contacts work best for you, purchasing contacts online can be more convenient and cost-effective than visiting your eye doctor to order. Many sites allow you to buy contacts as a one-time purchase or sign up for a subscription.
Here are some of the best sites to purchase contacts online:
1800 CONTACTS started 25 years ago, and have been pushing the vision industry in new directions ever since. They offer a huge selection of contact lenses, (probably more than your eye doctor), as well as highly rated 24/7 customer service.
You can buy contacts one box at a time or sign up for their super convenient subscription service so new contacts show up right when you need them.
LensDirect has been a leader in vision care products for almost 30 years. They are a family run business that constantly receives high rankings in industry reviews. They have a huge selection of contacts, eyeglasses, and sunglasses, and can ship products the same day.
AC Lens has also been providing services for over 25 years. They offer a large selection of contacts, eyeglasses, sunglasses, readers, and other eye care products. Their prices are consistently lower than most other online retailers.
Only certain contacts are FDA approved for extended wear. Most extended wear brands are only approved for 6 nights of continuous wear, while some are approved for up to 30 days/nights.
If your contacts are not approved for continuous wear you should never sleep in them. It could seriously damage your eyes. Also, not all contact lens wearers are eligible for extended wear contacts.
Speak with your eye doctor to find out more important safety information and to see if you are eligible.
How many hours a day can you wear contact lenses?
Most people can wear contacts comfortably for 14 to 16 hours per day. However, many eye care professionals recommend wearing contacts for no more than 12 hours a day. Follow any advice from your eye doctor.
Can I swim or shower in my contact lenses?
No, the FDA states that contact lenses should never be exposed to any water. This includes tap, bottled, distilled, lake, or ocean water. Water contains countless microorganisms that can cause eye infections, irritation, and even corneal ulcers.
Melody Huang is an optometrist and freelance health writer. Through her writing, Dr. Huang enjoys educating patients on how to lead healthier and happier lives. She also has an interest in Eastern medicine practices and learning about integrative medicine. When she’s not working, Dr. Huang loves reviewing new skin care products, trying interesting food recipes, or hanging with her adopted cats.
Michael is the content strategist and a lead content writer for Vision Center. With eight years of experience in the world of content strategy and creation, Michael specializes in medical copywriting and advanced research methodologies.
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