I admit it: I didn't think credit card companies could sink any lower.

I thought issuers had already introduced every foul trick imaginable. I even harbored hopes that new restrictions imposed by Congress and the Federal Reserve, would force card companies to shape up.

But their recent antics proved me wrong. Instead of cleaning up their act, issuers are innovating brand-new ways to jerk around their customers.

New fees, altered terms, abrupt account closures and unexplained rate increases are vivid illustrations of why credit card debt is considered toxic.

Of course, any debt can qualify as toxic if it has the potential to erode your financial well-being. Even a mortgage, which is generally considered good debt because it allows you to buy an asset that can appreciate, can become toxic if you can't afford the payments.

But debt is toxic by definition if any of the following is true:

• The lender can change rates and terms at any time, with little or no provocation.

• The standard or default interest rate is in the double digits, or higher, which typically prolongs the time you remain in debt.

• Initially easy payment terms encourage you to rack up more debt than you can comfortably repay.

The gloves are off

Payday and car-title loans are examples of extremely toxic debt, since their effective interest rates are in the triple digits. But the most common toxic debt for households today is credit card debt, and it's getting more poisonous by the day.

Just consider:

• Promises broken. Chase recently slapped a new $10-a-month service fee on customers who carried a balance but who weren't making new charges on their accounts. In many cases, the customers had taken advantage of balance transfer offers that promised a low rate until their debt was paid off. The smart way to use such offers is not to make new charges, since those accrue interest at a much higher rate. Chase didn't technically break its "life of the balance" promise, but the new fees certainly boost the effective cost of the debt.

• Guilt by association. American Express has been slashing credit limits on customers based at least in part on where they shop, where they live and what company holds their mortgage. Instead of being judged by your own behavior, in other words, you could be punished for shopping where high-risk people shop, living in an area of declining home values or getting your mortgage from a lender that also made subprime loans.

• Shuttered accounts. Many issuers are slamming shut accounts for lack of activity with little notice and no chance of appeal. Losing such unused accounts may not seem like a big deal until you consider the potential impact on your credit score. If the shuttered account is among your oldest or highest-limit cards, your credit scores could take a hit.

Clearly, the stakes are getting higher. A lousy economy and rising defaults have card issuers running scared. They will continue to use any means necessary to reduce their risk, regardless of the consequences to your finances.

It's time to ditch this and other toxic debt, once and for all.

6 steps to detoxifying your finances

The best way to pay off toxic debt is by yourself. Forget debt consolidation loans and other purported magic bullets, which may just keep you in debt longer. Typically, the cheapest and fastest way out is to tackle your toxic debt loan by loan or card by card, throwing as much money as you can at the highest-priority debt while making minimum payments on the rest.

List your debts, including:

• The balances you owe.

• The credit limits on each credit card.

• Your current interest rates and when they expire.

• Your minimum payments.

If you have payday or car title loans, you may not know the actual interest rate -- but it's likely in the triple digits. Make repaying those your first priority.

If you have any credit cards at or near their limits, consider tackling those next, since the high balances are hurting your credit scores. That could, in turn, cause your lenders to consider you at increased risk of default and lead to higher interest rates or more fees.

Otherwise, focus on the card with the highest interest rate. Once that's paid off, make the same monthly payment on your next-highest-rate card, and so on, until you're debt-free.

Throw every penny possible at your debt. If you have any savings or nonretirement investments, use the cash to pay down your debt. Sell stuff on Craigslist or eBay. Get a second job or consider freelancing on the side. Cut expenses wherever possible.

If you need ideas, check out the Smart Spending blog and MSN Money's Savings and Debt areas. Set up automatic transfers so these savings are transmitted regularly toward paying down your debts.

People are doing this every day, successfully.

Think twice about high-risk "solutions." Using your 401k or home equity to pay off credit card debt may be tempting, especially since you're able to get a lower rate -- sometimes a far lower rate -- than what you're paying on your toxic debt. But these loans are fraught with peril. If you lose your job, a 401k loan can become an inadvertent withdrawal, which will cost you big time in taxes, penalties and lost future returns.

You also should think twice about using precious home equity to pay off cards or loans; you've just turned unsecured debt that could be erased in bankruptcy into secured debt that can't. Even if you don't anticipate going broke, your home equity probably should be preserved in case you need to tap it in a real emergency. Still:

Lower rates can help. Check with your bank or credit union to see if you can get a personal loan to pay off high-rate debt. A personal loan at 13% or 14%, for example, is a much better deal than paying 30% on a credit card or continuing to pay fees on a payday loan accumulating at 400% a year. Peer-to-peer lending sites are another resource to try.

If you have good credit and the interest rate on your credit card is above 10%, you can try negotiating with credit card lenders for a lower rate. If your issuers won't cooperate, consider transferring your balances to another card or cards. But:

Trust no one. Scour the fine print of every balance transfer offer you consider, as well as every scrap of paper and e-mail message you subsequently receive from any issuer. Look for hidden traps, unexpected fees and sudden changes in the terms of your agreement. You may be able to preserve your current rate and terms by "opting out" of any changes and agreeing to close the account, but you have to notice the change in time to exercise this option.

Recognize when you're whipped. Not all toxic debt is payable. Your chances of paying off your debt are slim if:

• You're unemployed.

• You're struggling to pay your minimums.

• Your toxic debt approaches or exceeds your annual income.