Many people, having become familiar with their own healthcare needs and nuances, have seemingly become their own amateur healthcare professional. Over-the-counter (OTC) remedies and old prescriptions are kept organized in medicine chests, creating an impromptu apothecary. Everything from monthly headaches to recurrent sinus infections and conjunctivitis are cut off at the pass by savvy former patients who try at all costs to avoid the local urgent care waits. Taking the time to learn a bit about drug metabolism and pharmacology can help you to safely begin repetitive therapies and mix and match OTC preparations safely.
Expiration dates are used by manufacturers to inform people of the date by which they can guarantee both the potency and safety of a medication. Solid medications are more durable than liquid preparations that require refrigeration. Government studies in the past have illustrated shelf lives that outperform the stated expiration date in the majority of medications. However, given the fact that storage conditions vary, it is difficult to predict unilateral stability beyond those dates. Therefore, while you can likely conclude that a drug will be safe if taken post expiration, its efficacy might not be 100%. Medications like insulin and EpiPens should provoke strict adherence to expiration dates, while medications such as ibuprofen are likely to do the job despite passing their prime.
Drug Metabolism and Elimination
Simply put, metabolism is the breakdown of drugs in order to facilitate excretion, which is tantamount to their elimination. The majority of metabolism occurs in the liver (most often via an enzymatic pathway commonly referred to as the CYP450), and the majority of excretion occurs via the kidneys or bile (ultimately, the gut). Some drugs are broken down and then eliminated, and others are eliminated intact. Knowing if and how a medication is broken down and excreted can help you to understand safe drug combinations and dosages. For example, alcohol is metabolized via the same pathway (CYP450) as acetaminophen (Tylenol). While concomitant use isn’t necessarily dangerous, understanding that Tylenol might not be the best choice for analgesia following binge drinking is important. Also, knowing that you can safely alternate ibuprofen (Advil or Motrin) and acetaminophen in a febrile child (rather than increasing the frequency and/or dose of either one) can safely and comfortably get your child through a viral illness. Both the metabolism and excretion of drugs are affected by factors such as genetics, chronic disease, and age. Knowing your body as well as your common ailments (and their remedies) well before you have to use them in a crisis can help you safely reach into your medicine cabinet at midnight when you’re not in your doctor’s office to inquire.
Overdose and side effects
Medications can often be used together, but knowing what is in your arsenal and what to look out for in case of overuse/overdose or improperly mixed medications and substances can help you avoid a crisis. A ‘well stocked’ medicine cabinet often has drugs such as: antihistamines (for allergies; which can cause anticholinergic crisis in excess), dextromethorphan (for cough; which can lead to altered mental status and decreased breathing in excess or in combination with substances such as alcohol), analgesic (for pain; which can cause gut upset/ulcers, liver toxicity, acid/base disturbance depending on the type used) and antibiotics (for infection; which vary greatly in side effects and safety). Know your common medications and temper that knowledge with the state of your body, health and other substances used in the same timeframe (such as drugs and alcohol).
Knowing yourself and your medicine cabinet can be achieved safely. Many of us suffer from the same recurrent maladies (monthly headaches, urinary tract infections, seasonal allergies) and utilize the same or similar regimens for relief. If you take the time to research and ask your doctor about those medications, you can make responsible decisions even when you are not able to ask a healthcare professional ‘in the moment’. When in doubt, there’s always the ER or urgent care.