5 Things You Own That Cost More Than $500 a Gallon

— -- intro: Last year my mother-in-law sent me to the store to pick up some over-the-counter ointment for her dry eyes. When I saw the price for the tiny tube, I was floored. "What’s it made of?" I wondered. "Gold dust?" I tried to calculate the price per gallon in my head and quickly realized it was in the thousands.

We balk at the price of orange juice as it nears $6.50 a gallon, and no doubt grumbled about the price of gas when it hit almost $4 a gallon, or but those prices may seem like a bargain when compared to these everyday items, all of which cost more than $500 a gallon.

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Anything that costs more than $3.91 per ounce adds up to $500 a gallon. And you’d be surprised at what you’re using that costs that much. (Note: For this list, I’ve relied on prices on Amazon as of Oct. 23 unless noted otherwise.)

quicklist:title: Eye Drops — $3,336 per Gallontext:

Dry eyes? Allergies? If you suffer from either then, like me, you probably keep a bottle of eye drops handy at all times. Those tiny vials of liquid comfort aren’t cheap. For example, a bottle of Systane, the brand I carry because my eye doctor recommended it, runs $26.06 per ounce.

quicklist:title: Makeup — $704 per Gallontext: Most women will tell you that keeping up appearances can be expensive. Whether it’s higher prices for basics like shaving cream or shampoo designed for women, or pricier services like hair color, manicures or waxing, the costs of a beauty regimen add up.

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One example: liquid foundation. Even a relatively inexpensive brand, such as CoverGirl Clean, runs $5.50 for just an ounce.

quicklist:title: Printer Ink — $1,664 per Gallon (or More!)text:

Comparing the per ounce price of printer ink is nearly impossible since package labels don’t state the volume of ink contained within each cartridge. But Consumer Reports has researched it and according to this infographic and they pegged it at $13 to $75 per ounce. Even more disconcerting, their research has found that significant amounts of ink may be used for printer maintenance chores.

quicklist:title:'Safe' Sunscreen — $608 per Gallontext: You can buy generic sunscreen inexpensively if you go for generic brands or big bottles, but if you want to buy sunscreen that meets the Environmental Working Group’s standards for “safe sunscreen,” it’s going to cost you quite a bit more. For example, the sunscreen I purchased after reviewing that list, TruKid, runs $4.75 per ounce. I love it, but I live in Florida and at that price it is tempting to use a bargain brand.

quicklist:title: Insulin — at Least $36,903 per Gallontext:

According to the CDC, 29.1 million Americans have diabetes and and about 6 million use insulin, either alone or with oral medication. Dr. David Belk, a practicing physician and founder of TrueCostOfHealthcare.org, looked at the average prices all pharmacies paid in the U.S. the week of Oct. 8 (National Average Drug Acquisition Costs) and found that for the most commonly prescribed insulins, prices ranged from $9.75 to $9.80/ml to $21.51/ml. With insurance, of course, your copay may be lower, but many patients still struggle to pay the cost of this lifesaving medication.

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While you may not be buying gallons of these items at once, the cost can add up over time. And whether you are a small-business owner who relies on your home office printer to get work done, or a diabetic who needs insulin to stay healthy, you may find these purchases essential. If you charge them to a credit card and can’t pay them off in full, you’ll pay even more when you add in the cost of debt. You may even affect your credit scores, since credit card balances that total more than 20 to 25 percent of your available credit can affect your credit scores.

Any opinions expressed in this column are solely those of the author.