Medications and Nutrient Depletions: Part 2

Now that you know how drugs go through the ADME (Absorption-Distribution-Metabolism-Excretion) process, let’s first look at drugs that can affect the absorption of nutrients.

Absorption

Drugs that Cause Loss in Weight, Anorexia, Nausea, and Vomiting

People can get excited about weight loss—but losing weight as a side effect of medication is not healthy! You still need to eat well in order to stay healthy, and many of these medications prevent that healthy diet!

There are many different ways these medications can alter what you eat by affecting absorption—they may:

• Alter your sense of taste or smell
  • Examples: Heart medications (ACE inhibitors, calcium channel blockers), levodopa, anti-depressants
• Cause dry mouth
  • Examples: Some diuretics (water pills), antihistamines
• Cause anorexia or loss of appetite
  • Examples: Anticonvulsants, antidiabetics, anti-psychotics, opioids
• Cause difficulty in swallowing
  • Examples: Bisphosphonates, antibiotics, NSAIDs
• Cause nausea and/or vomiting by triggering chemoreceptors or the chemoreceptor trigger zone
  • Examples: Antibiotics, SSRIs and other anti-depressants, heart medications, antidiabetics, and drugs used to treat Alzheimer’s disease

Distribution

Remember, distribution is the process describing how different drugs can be delivered throughout the body—to do this, these drugs given orally—as most are—first need to be absorbed through the digestive system. This process can be disrupted by being slowed (constipation) or by being speeded up (diarrhea):

• Gastrointestinal mobility is the speed with which food (and drugs) can pass through the system. Drugs that cause constipation (eg. Opioids, some anti-depressants) can slow distribution because they increase the time spent in the digestive tract. Other drugs can cause diarrhea—this can speed up the time in the digestive tract, leaving insufficient time for distribution. Many antibiotics, anti-acid drugs (PPIs), and some antidiabetic agents cause diarrhea. But—in addition—many of the other ingredients used to prepare pills, tablets, and capsules use substances (eg. Sorbitol) that can cause diarrhea.

Metabolism and Excretion

In Part 1, we talked about the importance of First Pass Metabolism. That pattern of P450 enzymes can differ in each individual—and can affect not only how well a drug works in that individual but how long it stays in the system. Those P450 enzymes become even more important when several different drugs are used. Imagine that Drug A inhibits the P450 enzyme responsible for the metabolism of Drug B…that will mean that Drug B stays in your system longer than expected. While for some drugs that may not be a problem—for others, it may be the cause of adverse effects. Imagine the opposite too—if Drug A enhances the P450 enzyme responsible for the metabolism of Drug B…then Drug B is excreted faster than expected—and this could reduce its effectiveness. We recommend you consult with your healthcare provider and your pharmacist to determine if your particular combination of medications may be interacting in this way.

One final point about excretion—this can be affected by several different factors as well.

• Liver and kidney diseases
• Diet and water intake—a diet low in fiber and/or not drinking enough water can affect the excretion of various drugs
• The decree of acidity of the urine (the pH)
• Whether the drug is bound to protein in the blood

Specific Commonly Prescribed Drugs and the Nutrients they Deplete

The most common chronic conditions, according to the National Ambulatory Care Service Survey released by the National Center for Health Statistics, are high blood pressure, high blood lipids (fats), arthritis, diabetes, depression, asthma, heart disease, and chronic obstructive pulmonary disease (COPD).(1)  Rather surprisingly, there is not a lot of research concerning drug-nutrient interactions and depletions (incidentally, there is also not a lot of research concerning drug-drug interactions either…). In general, these nutrient depletions tend to occur mainly after long-term use, but that may not be true in some individuals with latent (sub-clinical) or the just-barely-below normal nutritional status. Magnesium levels are a case in point—magnesium is one of the most important minerals but is rarely measured, is difficult to accurately measure yet is believed to be one of the main “drivers” behind heart disease(2) and important in reducing complications in patients with type 2 diabetes.(3) Plant food is a major source of magnesium, but plants derive their magnesium from soils—and soils around the world have been found to be magnesium-deficient.(4)

But the very important question often asked, is “What can I do about these depletions?” First—talk to your doctor and pharmacist and get their “take” on your specific situation and see what they recommend—or if you can take an alternative medication that does not deplete that nutrient. Second, if the nutrient depleted is a vitamin, mineral or other nutrient available, consider taking a supplement that can replenish the nutrient or nutrients. Nutrition is always ideally best via the diet—but as you can see from the (lengthy…sorry!) information given, the drug itself may make it very difficult for a diet simply fortified with specific nutrient(s) to effectively replace those depleted! Third—realize that diet and lifestyle can often make a significant difference in your condition—particularly with high blood pressure, high blood lipids, diabetes, heart disease, and arthritis. If you improve your diet and exercise regularly, have your condition re-evaluated periodically. You may be able to decrease your dose of medication and not need to replace as many nutrients! Good deal—because you are likely to be feeling better all around!

We are beginning to learn more and more about these interactions. The most commonly prescribed drugs, along with the effects on specific nutrients, are listed in Table 1 below.(5)(6)