On this podcast episode, I discuss niacin pharmacology, adverse effects, drug interactions, and much more.
Niacin has historically been used to manage lipids but has fallen out of favor due to adverse effects, and newer, more effective therapies being developed.
Niacin can elevate uric acid. Be sure to use this medication cautiously in patients with gout.
Flushing is one of the most common adverse effects of niacin. High doses, immediate-release formulations, and the use of alcohol can increase the risk.
I discuss calcium carbonate pharmacology, adverse effects, drug interactions, and more in this podcast episode.
Calcium tends to have a constipating effect and the higher the dose, the more likely patients are to experience this adverse effect.
Binding interactions are a major problem with oral calcium carbonate. I lay out numerous examples of this on the podcast.
There are a few medications that can increase calcium levels in the blood. Thiazide diuretics are a commonly used antihypertensive that may contribute to hypercalcemia.
In this podcast episode, I discuss thiamine pharmacology and its important role in energy production.
In patients with alcohol use disorder, thiamine deficiency can be somewhat common.
Wernicke’s encephalopathy can result from thiamine deficiency in patients with alcohol use disorder.
Common symptoms from Wernicke’s encephalopathy can include confusion, lethargy, and other central nervous system issues. Thiamine replacement can help treat this issue.
On this episode of the podcast, I discuss my approach and strategies to handle grapefruit juice interactions.
Grapefruit juice causes drug interactions by inhibiting the CYP enzyme system. More specifically, it inhibits CYP3A4 which is responsible for the breakdown of many medications.
Quantity is always an important consideration when assessing grapefruit juice interactions. The more that is taken, typically, the more drug concentrations will be affected.
It is important to assess the use of grapefruit juice when your patient has a history of cardiovascular disease, cardiac conditions, pain, mental health disease, or gout as some medications used to treat these diseases can interact with grapefruit juice.
If you are looking for more content on drug food interactions, be sure to check out my book in the links below.
Folic acid is a water-soluble vitamin; compared to fat-soluble vitamins, accumulation is not as much of an issue. It is responsible for the formation of coenzymes, DNA synthesis, erythropoiesis, and certain metabolic processes. Due to the mechanism of folic acid, if there is a deficiency present, anemia can manifest. Although the recommended dietary intake is 0.2 mg, supplementation may be necessary. Some situations where supplementation may be desired are prevention of neural tube defects in pregnancy, patients suffering from alcohol abuse disorder, bariatric surgery patients, and certain types of GI disorders where malabsorption may be present. If a patient is taking certain medications folic acid supplementation may be necessary as well. Notable drugs where a patient may require folic acid include methotrexate and phenytoin.
The dosages used most often when supplementing folic acid are in the 1-5 mg range, and most of the time it will be 1 mg. Folic acid has a relatively safe adverse drug reaction profile. Some possible adverse drug reactions are flushing, malaise, erythema, skin rash, and hypersensitivity reactions. Although uncommon, the chance for an adverse drug reaction occurring increases as the dose increases. For monitoring folic acid, the normal levels can vary between 2-20 ng/mL, but they can vary based upon the lab. A type of anemia that can manifest with a folic acid deficiency is megaloblastic anemia. When assessing megaloblastic anemia, vitamin B12 levels should also be assessed.
Folic acid levels can be impacted by phenytoin, methotrexate, trimethoprim and sulfamethoxazole, sulfasalazine, triamterene, and alcohol. When a patient is only taking trimethoprim and sulfamethoxazole for acute treatment of a UTI, folic acid levels aren’t as concerning. Whenever it changes from acute treatment to prophylaxis, folic acid levels should be monitored more closely. Theoretically, folic acid can lower concentrations of phenytoin, and phenobarbital, so closer monitoring may be warranted.
Show notes provided by Chong Yol G Kim, PharmD Student.
Caffeine is a commonly used supplement and is found in many food and beverages. I discuss caffeine pharmacology, adverse effects, and drug interactions.
Caffeine can inhibit CYP1A2 and also be affected by CYP1A2 inhibitors. I discuss some examples in the podcast.
It is critical to inquire about caffeine intake when patients are reporting insomnia.
Caffeine has been associated with increases in pulse and blood pressure. Be sure to ask about caffeine intake when assessing these vital signs.
On this episode, I discuss magnesium pharmacology and the clinical applications. Magnesium plays numerous important functions in the body and you may see patients take these supplements under the direction of a healthcare professional and sometimes on their own.
It is very important to remember that magnesium can cause GI upset and diarrhea. This is often overlooked in our polypharmacy patient.
Magnesium can accumulate in renal disease. This is important to remember especially in patients who have a tendency to take a lot of supplements without discussing them with a healthcare professional.
PPI’s are a notorious cause of low magnesium. Loop diuretics can increase magnesium excretion and also cause low magnesium levels.
Magnesium can bind up numerous drugs reducing concentrations and leading to treatment failure. A few examples include quinolone antibiotics, tetracycline antibiotics, and levothyroxine.
Iron supplements frequently cause GI upset. Monitor patients for nausea, vomiting, and constipation issues.
There are three main salt forms of iron. Ferrous fumurate has the most elemental iron, ferrous sulfate (2nd most), and ferrous gluconate has the least.
Iron can bind up antibiotics and reduce their effectiveness. Two classic examples include the quinolone and tetracycline antibiotics.
Anemia can be caused by numerous concerns, however, iron deficiency is a very common cause.
Ferritin is a lab that we commonly monitor in a patient who may be iron deficient. Iron deficiency can also lead to symptoms of Restless Leg Syndrome.
