Q: I experienced a problem with “frozen” medication. Combivent Respimat inhalation spray was shipped to me during an unusually cold spell. I noticed I was not getting the same relief for my breathing, and the relief I did get didn’t last the expected six hours.

I called Boehringer Ingelheim, the manufacturer. The representative I spoke to instructed me to stop using the inhaled meds immediately. They shipped me a replacement right away. Is it safe to get mail-order medicine in the winter?

A: You raise a fascinating question. Most medicines are supposed to be maintained within a relatively narrow temperature range (68 to 77 degrees Fahrenheit). For short periods of time, it is generally OK if temperature fluctuates between 59 to 86 F.

During either winter or summer, shipped medications may spend hours outside those parameters. One woman wrote:

“My husband was sent some AndroGel by mail order, but we had to go out of town for a funeral at the last minute. The meds spent eight days riding around in a truck before they could be delivered.

“Routine blood tests revealed that the meds were no good. The manufacturer was so concerned that it tracked down exactly where the drugs had been and at what temperatures. Apparently, they spent too much time in temps over 85 degrees, so the company refunded our money.”

Q: I’ve been taking duloxetine (Cymbalta) for about nine years for depression. When I first started taking it, I was told I would be better in a year and could just stop taking it. Unfortunately, I found out the hard way that that isn’t true!

The side effects of trying to come off it are horrific. Missing even a day causes nausea, headaches and dizziness. When I’ve accidentally run out, I’ve landed in the hospital because I’ve been so ill.

I feel my personality has changed, and not for the better. I really need to get off this medication, but I’m scared stiff at the thought of being so sick. I never would have taken this medication if I’d have known how addictive it is.

A: Stopping almost any antidepressant suddenly can result in severe withdrawal symptoms. Many people report brain zaps, dizzy spells, nausea, headaches, sweating and visual disturbances. This can be extremely debilitating.

Gradual tapering over several months may reduce the discomfort. We provide more details and other approaches for supporting mental health in our “Guide to Dealing With Depression.” Anyone who would like a copy, please send $3 in check or money order with a long (No. 10), stamped (71 cents), self-addressed envelope to: Graedons’ People’s Pharmacy, No. E-7, P.O. Box 52027, Durham, NC 27717-2027. It also can be downloaded for $2 from our website: www.peoplespharmacy.com.

Q: My doctor recommended psyllium for double duty: to lower my cholesterol and to keep me regular. How does this laxative lower cholesterol?

A: Psyllium is fiber from the plantago plant. The soluble fiber binds to bile acids in the digestive tract, allowing you to eliminate excess cholesterol. While psyllium won't lower total cholesterol as much as statins can, it can lower this blood lipid anywhere from 9-15 points (Journal of Chiropractic Medicine, December 2017). Taking psyllium also may reduce levels of triglycerides and blood sugar.

In their column, Joe and Teresa Graedon answer letters from readers. Write to them in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email them via their website: www.PeoplesPharmacy.com. Their newest book is “Top Screwups Doctors Make and How to Avoid Them.”