Q: After knee-replacement surgery, my doctor told me to take three or four ibuprofen tablets every four hours for pain. It did not help the pain much, but I developed severe ringing in my ears. After a few years with no ibuprofen, the ringing has almost stopped.

A: NSAID pain relievers such as diclofenac (Voltaren), ibuprofen (Advil, Motrin, etc.), meloxicam (Mobic) and naproxen (Aleve, Naprosyn) all can affect hearing or trigger tinnitus (ringing in the ears). The Nurses’ Health Study queried nearly 56,000 women about their use of pain relievers over two decades (American Journal of Epidemiology, Jan. 1, 2017). Those who took acetaminophen or an NSAID at least twice a week for more than a year were about 10 percent more likely to have hearing loss.

Q: Most people think that the old- fashioned cough medicine terpin hydrate has been banned. That’s not true. Although it’s no longer kept in stock at pharmacies, it can be ordered from a compounding pharmacy.

Four years ago, I came down with a bad cold and wicked cough. I asked my doctor if he could write a prescription for terpin hydrate and was surprised that he was willing to do so. I contacted my local compounding pharmacy, and they said they don’t carry it in stock, but they would place a special order. They filled my prescription.

Last week, I came down with another bad cold and was coughing constantly. I went back to my doctor, who asked if the terpin hydrate had worked. When I said yes, he rewrote the prescription and the pharmacy filled it. Within 48 hours it made a HUGE difference, instead of taking three weeks for the cough to run its course.

A: Terpin hydrate was a popular cough medicine in the early 1900s. By the late 1980s, however, the Food and Drug Administration found inadequate evidence to support its continued sale.

This expectorant disappeared from pharmacy shelves, but compounding pharmacies might still make and dispense it. Like you, many readers remember it to be quite helpful for calming a hard-to-treat cough. It is made from oil of turpentine.

Q: I have had Hashimoto’s disease since the late ’90s. The doctor who diagnosed it said generic levothyroxine is fine as long as the pharmacy doesn’t change pharmaceutical suppliers.

How do you know when they change? Lately, my hair is thinning terribly and breaking off. I also have brain fog, constipation, aching joints and insomnia.

I just had a thyroid test, and my doctor said it was fine. He said maybe my pharmacy was buying from a different manufacturer. The pills smell different, but there’s no information on the bottle.

A: Hashimoto’s thyroiditis is an autoimmune condition in which the body attacks the thyroid gland. As a result, the gland loses its ability to produce adequate thyroid hormone.

The usual treatment is levothyroxine, also known as T4. Brand names are Levothroid, Levoxyl and Synthroid.

Any of these forms of levothyroxine can be helpful, but they are not always interchangeable. That is why your doctor recommended sticking with the same generic manufacturer. You will need to talk with the pharmacist about that.

Your doctor’s report that your thyroid is “fine” is not specific enough. You’ll want to get the actual results of your tests and keep track yourself.

Our revised Guide to Thyroid Hormones offers more details on interpreting test results and treating hypothyroid symptoms. It is available online at www.PeoplesPharmacy.com.