The co-authors of Invasion of the Prostate Snatchers, blog alternate posts weekly. We invite you to post your comments.

Tuesday, March 31, 2015

Medications for Prostate Cancer that Might Help and Probably Won’t Hurt


Do we have confidence in our prescription pills?  How can we really know that they are helping?   It partly depends on whether or not there is a benefit.  Fever disappears soon after starting an antibiotic.   PSA declines in men with prostate cancer who undergo hormone blockade.  Blood pressure is better after starting a new blood pressure medication.

We have confidence in these medications because there is a measurable benefit.  Seeing a benefit offsets our suspicions about potential side effects. Medication choices really boil down to a simple equation: balancing the benefit against the risk of side effects.

But sometimes it’s difficult to see the benefit, especially if the medication is being used because of the benefits were only reported in a population study showing and advantage of one group of people over another.  Baby aspirin is a good example. How do you really know that the pill you took today helped you dodge a heart attack?

Science and the Media
Interpreting scientific studies requires skill and training. But these days, the challenge is even greater because scientific studies are primarily reported in the media.  Unfortunately, media experts face tremendous temptations to make their stories more interesting. So they tend to overstate their importance.  As a result the general public is becoming very wary of supposed scientific finding.   

Considering Risk, What about Low Risk Medications that “Might” Work?
Few people have the time or skills to do their own research. But deciding “yea” or “nay” on a new medication can also be based on its perceived risk. If a medication is considered relatively safe, people with a chronic illness like prostate cancer may start thinking along the following lines: “I can’t be sure it will help, but at least it won’t hurt.”  This is a common mindset with vitamins and supplements because they are generally perceived to be harmless.*

Modifying the Down-Side Risks
This “why not” mindset comes into play when considering certain common generic medications that have been on the market so long their potential side effects are well known.  Specifically I am referring to four medications—aspirin, metformin (a diabetes medication), 5-alpha-reductase inhibitors like Avodart and Proscar, and Lipitor (a cholesterol drug).

In previous blogs I have presented arguments in favor of aspirin, Avodart and Proscar. In my next blog I’ll review some of the arguments for using metformin and Lipitor in patients with prostate cancer.

However, in the remainder of this blog I would like to outline an approach for reducing the risk of experiencing serious side effects:

1)     The greatest vigilance is necessary in the first few weeks after a new medicine is started.  When a medication causes side effects they usually appear fairly quickly.

2)     Generally, there is no rush. So why not begin at half dose? If after a few weeks or a month there are no negative side effects, the dosage can be gradually increased.

3)     Medication side effects follow specific patterns. Aspirin, for example, can cause intestinal bleeding.  So patients need to be carefully informed about the significance of any new symptoms of heartburn and the meaning of having black stools should they appear.

4)     Some side effects are only detected with blood tests.  Everyone who starts a cholesterol drug—Lipitor for example—needs to have liver function tested within a month or so.  Liver problems heal quickly if the side effects are detected and the medication is stopped in a timely fashion. It can be dangerous if negative effects persist undetected.       
*Ironically, in the absence of overt deficiency, when vitamin supplementation is subject to careful testing it sometimes has been shown to be deleterious.   Vitamin E is one good example. In a large randomized, double-blind placebo-controlled trial, prostate cancer mortality was higher in the men who took vitamin E compared to those who took a placebo. 

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