Deadly drug shortages: Are you at risk?

Drugstore shelves may groan under the weight of all those pill bottles, but the scary truth is that more than 100 medicines are now in short supply. The danger isn't just theoretical. In 2010, several Americans died because they were unable to get the drug they needed, Dr. Erin R. Fox, manager of the University of Utah Hospitals & Clinics drug information service, tells CBS News.

Drug shortages happen for various reasons. Often the problem involves injectable chemotherapy drugs made by a single manufacturer. If that company runs into problems, it may take awhile for other drug makers to fill the void.

Keep clicking to see 10 drugs that are now in dangerously short supply. If a drug you rely on is on the list, Dr. Fox recommends consulting your doctor or pharmacist.

Zostavax

This shingles-preventing vaccine is recommended for everyone over the age of 50. But it's been in short supply for a year now, and shipments are six months behind schedule, according to Dr. Fox. Merck is the only manufacturer of Zostavax.

Cytarabine

Cytarabine is an injectable chemotherapy drug that is often used to treat leukemia. There are three manufacturers of cytarabine, but all are having trouble keeping up with demand. The shortage of cytarabine has delayed treatment for some patients, Dr. Fox says.

Leucovorin

Leucovorin is used to treat colorectal cancer, non-Hodgkin lymphoma, and osteogenic sarcoma, a cancer that often strikes children. All three of the companies that make this injectable drug are having supply problems, Dr. Fox says. An alternative drug known as levoleucovorin injection is also in short supply - though the FDA has identified a source of the drug from Italy.

Foscarnet

Foscarnet is of critical importance in the treatment of cytomegalovirus, a potentially blinding eye infection. The maker of forscarnet, Hospira, is having trouble supplying it. To make sure patients didn't go without the drug, the FDA has allowed importation of Foscavir, a product from the United Kingdom.

Norepinephrine

A real life-saver, norepinephrine maintains blood pressure in critically ill patients, including those in intensive care units. It's the only drug of its type, and in many cases there are no good alternatives. At one time three companies pumped out plenty of norepinephrine. But two are having manufacturing problems, leaving only one company to try to meet the demand.

Neostigmine

Anesthesiologists rely on neostigmine to reverse the action of "paralyzing" agents they use during surgery. But it's in short supply, and so is an alternative drug called edrophonium.

Concentrated sodium chloride

Doctors use this injectable drug to prevent the buildup of pressure within the skull in critically ill patients, including those who have sustained traumatic brain injuries and those nourished via total parenteral nutrition (tube feeding) because they cannot eat.

Thiotepa

Thiotepa injection is used to treat a variety of cancers, including sarcomas in children. The only supplier of the drug is out of it and unlikely to have any more for several weeks, Dr. Fox says. That means cancer centers won't be able to treat children for some time.

Bleomycin

Bleomycin is an injectable chemotherapy drug used for testicular cancer, head and neck cancers, cervical cancer, Hodgkin disease, and non-Hodgkin lymphoma. There are four suppliers, but three are beset by problems, Dr. Fox says.

Methylphenidate

A stimulant drug, methylphenidate is used for attention-deficit hyperactivity disorder (ADHD) and narcolepsy, a condition that causes people to fall asleep suddenly, without warning. Several manufacturers have product on back order, meaning patients may have to switch to an alternative medication - which can be highly disruptive.