Real Life Pharmacology - Pharmacology Education for Health Care Professionals

Testosterone replacement is primarily utilized in patients with hypogonadism. I discuss testosterone pharmacology, adverse effects, and drug interactions on this podcast episode. Testosterone is a controlled substance because it is most often diverted for its potential to build muscle in athletes for competitive sports. There is cardiovascular risks associated with the use of testosterone. Testost...

Morphine has opioid agonist activity that can cause respiratory depression and death in overdose. Morphine-6-glucuronide is the metabolite that can accumulate and cause CNS toxicity in renal failure. Be aware of CNS depressants that may enhance the effect of morphine and other opioids. Some examples of CNS depressants include gabapentin, benzodiazepines, older antihistamine, skeletal muscle relaxa...

Prasugrel is a P2Y12 inhibitor that is used in the setting of ACS. Be aware of patients who may be taking over the counter medications that can increase their bleed risk while taking prasugrel. Prasugrel is on the Beers list and in general, should be avoided in most situations for patients who are 75 years of age or older. Morphine has the potential to impact antiplatelet agents like prasugrel and...

Mirabegron is a beta-3 agonist that can help relax bladder smooth muscle and manage symptoms of overactive bladder. Mirabegron inhibits CYP2D6 which can negatively impact the effectiveness of tamoxifen. I discuss this in greater detail in the podcast. Tramadol and codeine effectiveness can be impacted by mirabegron. Be aware of this when using this medication. By inhibiting CYP2D6, mirabegron can...

Erythromycin uniquely has some potential benefit in the setting of gastroparesis. Azithromycin you will likely not see used for this indication. Erythromycin binds the 50s subunit and ultimately prevents protein synthesis which is necessary for bacteria to grow and replicate. QTc prolongation is a risk with all macrolide antibiotics (erythromycin included). By inhibiting CYP3A4, erythromycin can b...

Naloxone is a life saving drug that can help manage an opioid overdose situation. Naloxone blocks opioids receptors so opioid agonists cannot bind there. One of the biggest risks with opioid overdose includes respiratory depression. Naloxone can help reduce the risk of this if administered in a timely manner. IV naloxone will have the quickest physiological onset of action, but nasal naloxone may...

Prochlorperazine has several potential mechanisms of action. It can block dopamine and alpha receptors as well as have anticholinergic effects. Prochlorperazine is classified as an antipsychotic and antiemetic. It is very seldom used as an antipsychotic in clinical practice and more used for its antiemetic effects. Because of the anticholinergic activity of prochlorperazine, there is potential for...

Buspirone is an anti-anxiety medication that has the potential of having some serotonin agonist activity. Buspirone has a very high first-pass metabolism. This means that the body breaks much of the medication down prior to it getting into the systemic circulation. Buspirone is broken down by CYP3A4, so concomitant use with inhibitors or inducers can alter its concentrations Buspirone should not b...

Ondansetron (Zofran) is a medication used for nausea and vomiting. In this episode, I lay out the pharmacology, adverse effects, drug interactions and more! Ondansetron has been reported to increase the risk of serotonin syndrome. I discuss this further on the podcast. Ondansetron can exacerbate QTc prolongation. Keep an eye out for patients who may have risk factors or be on other medications tha...

On this episode “Acyclovir Pharmacology” I discuss the mechanism of action, important monitoring parameters, and drug interactions with acyclovir. I discuss why acyclovir has to be dosed so many times per day. Acyclovir can inhibit CYP1A2 which can impact a few drugs. I discuss a couple of those examples on this podcast episode. GI effects are one of the more common side effects of acy...

Benzodiazepines act by enhancing the effect of GABA, an inhibitory neurotransmitter. Benzodiazepines can cause confusion, sedation, and respiratory depression. There are many potential indications for benzodiazepines. They can be used in anxiety, status epilepticus, insomnia, and alcohol withdrawal amongst other things. There is a boxed warning for the use of opioids with benzodiazepines. The prim...

Celecoxib is easy to remember as its mechanism of action is “COX”-2 Inhibition. This can result in result in reduced prostaglandin formation and help with pain and inflammation. Kidney function is important to monitor in our patient on celecoxib. It is especially important in patients taking ACE inhibitors, ARBs, and/or diuretics. While GI bleed may be less likely with celecoxib compar...

Oseltamivir is an antiviral agent that is indicated for the treatment and prophylaxis of influenza. It is important to remember that oseltamivir is cleared at least in part by the kidney and dose adjustments should be made based upon kidney function. There is a low potential that oseltamivir could contribute to psych issues like delirium. Probenecid has the potential to raise the concentrations of...

Dolutegravir is an integrase inhibitor that is used in the management of HIV infection/ Carbamazepine along with other enzyme inducers can substantially lower the concentrations of dolutegravir. Dolutegravir can potentially increase blood sugars, this should be closely monitored in our patients with diabetes. CNS adverse effects like insomnia and dizziness can happen with dolutegravir. Be sure to...

On this podcast episode, I cover medroxyprogesterone acetate injection pharmacology (DMPA or Depo-Provera) Medroxyprogesterone acetate injection is given every three months for the prevention of pregnancy. Medroxyprogesterone acetate has a boxed warning for its risk of causing low bone mineral density. Classic enzyme inducers can cause lower concentrations of medroxyprogesterone which can potentia...

Budesonide/formoterol inhalation is sold under the brand name Symbicort. Budesonide/formoterol is a combination agent that is used in the management of COPD and asthma. Budesonide/formoterol is a combination of an inhaled corticosteroid and long-acting beta-agonist. GINA guidelines now allow for the use of budesonide/formoterol in the management of acute asthma exacerbation. Be sure to check out o...

Benztropine is a highly anticholinergic medication that is primarily used for movement disorders. Antipsychotics can cause extrapyramidal adverse effects that can help be managed with benztropine. Because benztropine is highly anticholinergic, it can cause dry eyes, dry mouth, urinary retention, constipation and contribute to falls and confusion, particularly in our elderly population. While benzt...

Budesonide is a corticosteroid that can be given orally or rectally for management of Crohn’s disease or ulcerative colitis. Because budesonide has a high first pass metabolism, the relative impact of systemic effects may be less than other steroids like prednisone. Remember that CYP3A4 inhibitors can increase the concentrations of budesonide. I discuss this further on the podcast. Different...

Cimetidine blocks histamine 2 receptors which can suppress acid production and reduce symptoms of heartburn. One of the major downsides to cimetidine is that it has a ton of drug interactions. I discuss many of the common ones in this episode. Cimetidine is one of a few drugs that has the potential to cause gynecomastia. I discuss the mechanism of this adverse effect in this episode. Phenytoin con...

Clopidogrel is an antiplatelet agent that is often used in combination with aspirin to help reduce the risk of an MI. The risk of bleed is a high priority with the use of clopidogrel. Patients must be monitored for signs and symptoms of bleeding and bruising. Clopidogrel is a prodrug that is converted to its active metabolite by CYP2C19. Fluconazole can inhibit CYP2C19 which may reduce the effecti...

Sulfasalazine is a medication that can be used for diseases like rheumatoid arthritis, Crohn’s disease, and Ulcerative Colitis. Because sulfasalazine can cause GI upset, this is a major reason why we try to break up the dose and give it multiple (at least two) times per day. LFT and CBC monitoring are recommended with sulfasalazine due to its low potential to cause liver dysfunction, aplasti...

On this episode, I discuss the pharmacology of cholestyramine. Cholestyramine was originally developed as an agent to manage cholesterol, but has fallen out of favor for some of the more effective agents like statins. Cholestyramine is notorious for binding drug interactions. It can reduce concentrations of drugs like amiodarone, digoxin, oral contraceptives, immunosuppressive and many more! In pa...

Rifampin is classified as an antibiotic and an antituberculosis agent. It primarily works by inhibiting bacterial RNA polymerase. While not extremely common, rifampin is well known to cause hepatic dysfunction. You should remind patients who are taking rifampin that it can alter the color of tears, sweat, saliva and urine. It can change these fluids to a reddish/brown color. Rifampin is very well...

Heparin is an interesting drug with a lot of unique clinical quirks. This drug ultimately inhibits the formation of fibrin. Fibrin is an essential component of a blood clot. Because heparin has blood thinning effects, it is critical to assess a patient’s bleed risk. Look out for other agents that may increase the risk of bleeding. Examples include; NSAIDs, antiplatelet agents, and other anti...

On this episode, I discuss montelukast pharmacology Montelukast is a leukotriene receptor antagonist. Leukotrienes play an important role in causing inflammation and smooth muscle contraction in asthma and allergic rhinitis. Because montelukast blocks the effects of leukotrienes, it can be advantageous to use this medication for allergies and asthma. It is important to remind patients that montelu...