Most of you know I’m a nurse and love all things health. It’s a huge pet peeve when I read books, and the situations that characters go through either should have killed them or at least incapacitated them. Instead, they carry on with their day to day activities.
As authors, we do SO much research; it’s easy to see how this can fall through the cracks. So, I’m here to help! Send me your medical questions, and I’ll help you sort them out, so your book can be even better!
My first question comes from the wonderfully supportive Alex on Twitter. He wants to know about mixing coffee and pills. I’m going to go ahead and assume this isn’t about the writer, but about a cuppa joe loving character in your book ;) This is a tough one since there are so many medications that can be affected by coffee, but I’ll break it down.
So, we’ll stick with just the caffeine aspect of coffee, as that’s the active ingredient most likely to interact with medications. In general, coffee is considered pretty safe, healthy even (writers everywhere, rejoice!).
If you struggle with anxiety, caffeine can certainly make it worse. It can also be a concern for people with heart issues. So if your character has anxiety, they could love coffee, but maybe they notice their heart racing, tightness in their chest, runaway thoughts, jittering leg, etc. If they have heart issues, maybe their doctor or spouse is always on them about cutting out their daily cup of the nectar of the gods, but the character keeps sneaking it. It can also cause bowel issues if your character has IBS… so… I’ll let you figure out that scenario.
Mixing coffee with alcohol can be dangerous, but is not uncommon. Alcohol basically keeps your liver busy, so it isn’t able to break down caffeine as quickly, leading to prolonged effects, and sometimes dangerously high levels of circulating caffeine.
What your character will experience: Your character would be edgy/irritable, shaky, have a killer headache, and that racing heart/tight chest.
Similar to alcohol, other medications can affect how long it takes the body to break down caffeine. These include:
- Certain antibiotics
- Birth control pills
- Drugs used to treat chronic alcoholism (so if your character is a recovering alcoholic, they might be on medication that prevents them from getting drunk when they drink, but they also aren’t supposed to have coffee with it. They might really struggle with that)
- OCD medications
- Cardiac medications (e.g. calcium channel blockers, some antiarrhythmics)
For some medications, it’s the opposite problem of alcohol: the caffeine prevents the body from breaking down the medication, leading to higher levels of the drug staying in your system. This can be super dangerous. These medications include:
- Schizophrenia medications
- ALS (Amyotrophic lateral sclerosis) medications
- Asthma/ COPD medications.
What your character will experience: The effects of the medication will last longer, and/or med levels will be higher in your system. The specific effects will depend on the drug but think longer, bigger, etc.
Lithium, a popular medication for treating bipolar disorder, is broken down and excreted more quickly when you consume caffeine, making it less effective.
Because caffeine is a stimulant, other stimulant medications can be a dangerous mix. Your character will be shaky, trembling, have a racing heart, etc.
Caffeine blocks the effect of certain medications, making them less effective, or not effective at all. These include:
- Anti-clotting medications
- Anti-arrhythmia medications (drugs used to keep your heart beating in a proper rhythm)
- Some vitamins (including vitamin C)
- Medications used to help you sleep.
What your character will experience: Your character will take their medication and not get the expected results. For example: if it’s sleeping medication, they will be laying in bed, not able to sleep, and maybe take more medication (dangerous).
Okay, that was a lot of information! I hope this helps add some depth to your coffee-addicted characters.
Sources: https://www.bmj.com/content/359/bmj.j5381; https://www.bmj.com/content/360/bmj.k194; https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5481750/; https://www.rxlist.com/coffee/supplements.htm; https://www.caffeineinformer.com/caffeine-drug-interactions