Home » Coffee with Allergy Pills (Chlorpheniramine): Dos & Don’ts

Coffee with Allergy Pills (Chlorpheniramine): Dos & Don’ts

Jacob Yaze

November 7, 2025

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Understanding The Role Of Sedating Antihistamines In Allergy Relief

First-generation antihistamines are powerful, practical—and famously sleepy. If spring blooms or dusty rooms send your nose into overdrive, there’s a good chance you’ve met this family: chlorpheniramine, diphenhydramine, brompheniramine, carbinoxamine, clemastine, hydroxyzine, and promethazine. They block histamine fast and predictably, turning down sneezing, itch, and watery eyes. Coffee, meanwhile, is your morning ritual with opinions: caffeine for alertness, organic acids that can poke at a sensitive stomach, and a swirl of aromatic polyphenols that make the cup feel like “you.” Putting them together is less about strict rules and more about rhythm—timing, portion, brew style, and bean choice.

Two truths can absolutely live together: sedating antihistamines can help you breathe easier, and coffee can help you feel awake and human again. The tricky part is that the combo can tug in opposite directions. For some people, a small, gentle cup takes the edge off the antihistamine haze without tipping into jitters. For others, caffeine later in the day quietly cancels the sleep benefit they wanted from the medication—or adds a hint of anxiety, palpitations, or that “wired-but-not-great” feeling. Your job (and mine) is to make the benefits stack, not clash.

The easiest way to do that is to make coffee calmer by design. Think “soft, steady lift” instead of “fast spike.” A smoother brew method can help you naturally sip slower and avoid that sudden rush; a clean, mellow cup from something like the Behmor Brazen Plus Coffee Brewer tends to feel more predictable than grabbing the strongest thing you can make and drinking it like it’s a timer. And if you love espresso but notice it hits you too sharply on sedating days, shifting to a small milk-forward drink (or simply watering it down into an Americano you sip slowly) can make the same caffeine feel gentler.

Timing is the second lever. If your antihistamine is taken at night for sleep, keep coffee earlier and treat the afternoon like a caffeine boundary. If you still crave the comfort later, swap the ritual to decaf so you keep the warmth and aroma without pulling your brain awake. A decaf that actually tastes satisfying—like Colectivo Coffee Decaf “Sugarcane”—can make that late-day cup feel like a treat instead of a compromise. If you’re sensitive and want an even quieter option, half-caff can be a gentle middle lane; Caribou Coffee Half Caff is the kind of switch that gives you the ritual and a little lift, without the full “caffeine loudness.”

Hydration is the quiet third lever that makes the whole combo feel steadier. Sedating antihistamines plus dry air can leave you feeling parched and headachy, and coffee can nudge that along. Pair each cup with water, and it often reduces the “racing heart when I stand up fast” feeling. If you want that to be automatic, keep a bottle you’ll actually use within reach—like the Stanley IceFlow Flip Straw Tumbler. And if your throat feels dry or scratchy (common with allergies), adding moisture at night can make mornings easier; a bedside humidifier like the Honeywell Cool Mist Humidifier can help you wake up less “crispy.”

So the playbook is simple: make the coffee smaller and smoother, keep it earlier if sleep is the goal, hydrate alongside it, and choose decaf/half-caff when you want comfort more than stimulation. You’ll know you nailed it when the day feels predictable: clear enough to function, calm enough to sleep, and still enjoyable.

Start with timing. If you want daytime clarity, keep coffee earlier and pick a smaller, smoother cup (paper-filtered drip or pour-over tends to be kindest). If your goal is sleep, take the antihistamine in the evening and keep afternoon coffee light—or choose decaf/half-caff. Next, consider the stomach. Both caffeine and anticholinergic antihistamines can dry you out a bit; sip water as your default sidecar and avoid big, fast gulps of very hot coffee. Finally, pick beans that are friendly to your goals: low-acid decaf or balanced half-caff for calmer stomachs and steadier nerves; smooth-medium roasts if you tolerate caffeine well.

Most importantly, personalize. Notice patterns: Does coffee before the dose feel different than coffee after? Does one large mug bother you more than two small ones? Do darker, low-acid decafs keep the ritual without the “buzz”? With a few tiny adjustments—spacing the pill and the pour, shrinking the mug, choosing a gentler roast—you can keep the cup you love and the relief you need. The table below gives you a quick, at-a-glance guide for the common first-gen antihistamines, including a “safest beans” pick for each (chosen to be low-acid, decaf, or otherwise “calmer”). Use it as a friendly compass—and keep listening to your own body.

*“Safest beans” = typically low-acid, decaf, or half-caff options that keep the ritual but reduce jitters, reflux, and sleep interference. Personalize to tolerance and clinician advice.

A Brief Overview Of First-Generation Sedating Antihistamines

First-generation antihistamines are the “old classics” people reach for when hay fever, hives, or a stubborn cold make life miserable. Medications like diphenhydramine (Benadryl®), chlorpheniramine (Chlor-Trimeton®), brompheniramine (Dimetapp®, Dimetane®), carbinoxamine (Karbinal ER®, RyVent®), clemastine (Tavist®), and hydroxyzine (Atarax®, Vistaril®) all live in this family. (Wikipedia)

They work by blocking H1 histamine receptors. Histamine is one of the main chemical messengers the immune system releases during an allergic response; at H1 receptors, it causes itching, sneezing, watery eyes, a runny nose, and sometimes hives or swelling. By antagonising H1 receptors all over the body, these drugs blunt those symptoms. (PMC)

The catch is that first-generation molecules are small, lipophilic, and not very selective. They cross the blood–brain barrier easily, and they also block muscarinic (acetylcholine) receptors. That’s why, along with allergy relief, you see:

• Sedation and impaired alertness
• Slowed reaction time and reduced psychomotor performance
• Anticholinergic effects such as dry mouth, blurred vision, constipation, and urinary retention(PMC)

Reviews from allergy societies and pharmacology texts repeatedly highlight that these older antihistamines can significantly impair driving, school performance, and work productivity, even at normal doses (PMC). In older adults, they’re listed as “potentially inappropriate medications” because long-term use is linked to confusion, falls, and even increased dementia risk due to cumulative anticholinergic burden. (Wikipedia)

Despite that, first-generation antihistamines are still widely used because they’re:

• Inexpensive and available over the counter
• Effective for acute allergic reactions, insect stings, and some kinds of cough linked to post-nasal drip
• Useful for short-term insomnia (diphenhydramine) or itching and anxiety (hydroxyzine)(DrugBank)

The modern approach is usually to reserve them for brief, targeted use—night-time allergy flares, a long flight, a bad cold—rather than as daily long-term therapy, especially if you drive, operate machinery, care for children, or are older than 65. Second-generation options like cetirizine, loratadine, and fexofenadine provide similar allergy control with much less sedation, but they don’t replace first-generation drugs in every scenario . (PMC)

Into this picture walks coffee. Because caffeine is famous for “waking you up,” many people naturally wonder if their morning brew can offset the drowsiness from these sedating antihistamines—or whether the two might clash in dangerous ways. To unpack that, we need to look at how caffeine works on the brain and how it overlaps with the side-effect profile of these medicines.

How Coffee Interacts With First-Generation Antiallergic Medication

Coffee’s main psychoactive ingredient, caffeine, is a non-selective adenosine receptor antagonist. As you go about your day, adenosine gradually builds up in the brain and binds to A1 and A2A receptors, promoting drowsiness and “sleep pressure.” Caffeine slips into those receptors without activating them, blocking adenosine’s calming signal and temporarily increasing alertness. (Wikipedia)

Sedating antihistamines work through a different pathway but cause a similar result—sleepiness. They block H1 receptors in the brain, suppressing wake-promoting histamine signalling and adding anticholinergic effects on top. (PMC)

When you combine the two, you essentially have one drug pushing you toward sleep and another trying to push you away from it. A few key points emerge from the available evidence and interaction databases:

• Formal interaction checkers generally list no major pharmacokinetic interaction between caffeine and diphenhydramine (Benadryl) or other first-generation antihistamines. One consumer-facing interaction report notes no known interaction between Benadryl and caffeine, but still advises standard caution. (Drugs.com)
• Professional drug references note that diphenhydramine increases and caffeine decreases sedation, and recommend monitoring because the net clinical effect can be hard to predict. (Medscape)

In real life, that means coffee may make you feel a bit less drowsy, but it does not fully cancel the cognitive and psychomotor impairment caused by a sedating antihistamine. Studies with other sedatives show that people who combine stimulants with CNS depressants often feel more awake while still performing poorly on driving simulators and reaction-time tests. The brain is still under the influence; the stimulant just hides some of the warning signals.

There are also overlapping side effects to consider:

• Both caffeine and first-generation antihistamines can increase heart rate; one via sympathetic stimulation, the other via anticholinergic effects. (DrugBank)
• Caffeine is notorious for worsening anxiety, tremor, and insomnia, while drugs like hydroxyzine or diphenhydramine are sometimes prescribed for anxiety or as a nighttime sedative (Mayo Clinic)
• Both can irritate the stomach in susceptible people, especially on an empty stomach.

So you get a tug-of-war: coffee may partially clear your head, but at the cost of more jitteriness, palpitations, or poor sleep. Meanwhile, the antihistamine’s effects on coordination, reaction time, and decision-making remain—just better disguised.

The practical takeaway: enjoying coffee while taking a first-generation antihistamine is not automatically unsafe, but it’s wise to assume you’re still sedated even if the caffeine makes you feel okay. Avoid driving, climbing ladders, supervising small children alone, or doing other high-risk tasks until you know exactly how that combination feels in your body, and always within the dose limits your clinician recommends.

Precautions And Potential Risks Involved In Combining Coffee With First-Generation Sedating Antihistamines

For most healthy adults, an occasional dose of a sedating antihistamine and a cup of coffee isn’t a disaster. But there are specific risk zones where the combo deserves extra respect.

Masked impairment

The biggest issue is false confidence. Caffeine lifts subjective sleepiness, but it doesn’t magically restore full cognitive or motor function. Sedating antihistamines can impair reaction times, divided attention, and decision-making—exactly the skills you need for safe driving or operating machinery. (PMC)

Mixing coffee with these meds may leave you feeling “OK to drive” when you’re still objectively slower. That’s particularly risky at night, on long trips, or if alcohol is involved. Many experts recommend never relying on caffeine to counteract medication-induced drowsiness when safety-critical tasks are on the line.

Cardiovascular and autonomic effects

First-generation antihistamines, especially in higher doses, can cause tachycardia and changes in blood pressure due to anticholinergic activity. (DrugBank) Caffeine is a mild cardiac stimulant: it can raise heart rate and blood pressure temporarily, particularly in people who aren’t habitual users or who consume large doses. (Wikipedia)

For most young, otherwise healthy people, this isn’t dramatic, but in those with arrhythmias, uncontrolled hypertension, structural heart disease, or on multiple QT-prolonging drugs, the combination could tip things in the wrong direction. Anyone with known cardiac issues should run their caffeine and antihistamine use past a clinician.

Worsening of underlying conditions

These older antihistamines are contraindicated or used cautiously in several groups:

• People with narrow-angle glaucoma, urinary retention, or significant prostate enlargement
• Patients with cognitive impairment or at high risk of falls (especially older adults)
• Those with severe liver disease or concomitant CNS depressant use (opioids, benzodiazepines, alcohol)(FP Notebook)

Caffeine can worsen anxiety, panic symptoms, tremors, and insomnia, which may counteract the anxiolytic or sedative purposes of hydroxyzine or diphenhydramine. (Mayo Clinic)

Sleep disruption

If you’re taking a sedating antihistamine at night—perhaps diphenhydramine as part of a “PM” pain reliever or hydroxyzine for itching and sleep—late-day or evening coffee can blunt the sleep-promoting effect and lead to fragmented, poor-quality sleep. Over time, that can worsen allergic symptoms, mood, pain, and cardiometabolic health.

Practical safety tips

• Limit caffeine to earlier in the day when using sedating antihistamines, and stay within typical safety limits (~400 mg/day for healthy adults, less in pregnancy or heart disease).
• Avoid alcohol and other sedatives; combining several CNS depressants is much riskier than adding coffee.
• Assume that, even with coffee on board, you’re not at 100% reaction speed; postpone driving, climbing, or high-risk hobbies.
• In older adults, or in anyone with complex health issues, talk with a clinician about whether a non-sedating second-generation antihistamine might be safer for daily use.

The goal is not to scare you away from your favourite beverage, but to approach the coffee–antihistamine combo with a clear understanding of what each is doing in your body.

Coffee and Brompheniramine

Brompheniramine is a first-generation antihistamine commonly found in multi-symptom cold preparations and allergy syrups. In many countries, it appears in products like Dimetapp® or Dimetane®, often combined with decongestants such as pseudoephedrine. (WebMD)

Pharmacologically, brompheniramine is a histamine H1 receptor antagonist with moderate anticholinergic activity—it dries up nasal secretions but also causes drowsiness, dry mouth, blurred vision, and increased heart rate. (DrugBank) It readily crosses the blood–brain barrier, and like other first-generation agents, it appears on anticholinergic-burden lists linked to cognitive impairment with long-term use in older adults. (Wikipedia)

Brompheniramine is metabolised in the liver via cytochrome P450 enzymes, though specific isoenzymes are less well characterised than for some newer drugs. (Wikipedia) There’s no clear evidence that caffeine or coffee meaningfully alters metabolism at ordinary doses, and major interaction checkers don’t flag a direct pharmacokinetic problem.

So what happens when you add coffee?

• Subjective alertness: A cup of coffee may take the edge off brompheniramine-induced grogginess, especially if you’ve taken a nighttime dose and are facing a workday. But the underlying H1 and muscarinic blockade is still there; your reaction times and coordination may remain impaired even if you feel “awake enough.”
• Heart rate and dryness: Both brompheniramine and caffeine can raise heart rate, through anticholinergic effects, the former via adenosine antagonism and sympathetic stimulation. In someone already tachycardic from a viral illness or decongestants, adding strong coffee may be uncomfortable. Dry mouth and mild dehydration from both coffee’s diuretic effect and brompheniramine’s anticholinergic action can also stack up, so drinking water alongside coffee is wise.( DrugBank)

If you’re using a brompheniramine-containing product for a heavy cold, consider these practical tips:

• Use nighttime formulations for the most sedating doses and keep coffee to the morning, well separated from your last dose.
• Choose filtered coffee, and keep the dose modest—you’re probably already fighting poor sleep from congestion, so you don’t want caffeine to make things worse.
• Avoid driving or operating machinery if you still feel foggy, no matter how much coffee you’ve had.

For occasional short-term use in otherwise healthy adults, the brompheniramine–coffee combination is usually manageable with common sense. But in older adults, or if you’re on multiple anticholinergic medications, it’s worth asking your clinician whether a less sedating allergy option might be safer overall.

Coffee and Carbinoxamine Maleate

Carbinoxamine maleate is another first-generation H1 antihistamine, used for allergic rhinitis, chronic urticaria, and sometimes more complex allergic skin conditions. You may encounter it under brand names like Karbinal ER® (extended-release oral suspension), Clistin®, or RyVent®.(Drugs.com)

Carbinoxamine exhibits clear sedative and anticholinergic properties—the official prescribing information describes it as an H1 receptor antagonist with “drying” and sedative actions (Drugs.com) Patient information from major centres like Mayo Clinic emphasises that it can make you “dizzy, drowsy, or less alert than normal,” and warns patients not to drive or operate dangerous machinery until they know how they rereact(Mayo Clinic)

Because Karbinal ER® is long-acting, a single dose can produce sedation for much of the day or night. That’s helpful if you’re miserable with round-the-clock itching, but it also means that a morning coffee may be fighting a slowly declining sedative effect for hours.

From an interaction standpoint:

• Drug-interaction databases focus primarily on additive CNS depression when carbinoxamine is combined with other sedatives, opioids, or alcohol. (DrugBank)
• Caffeine is not highlighted as a major concern, but the same general principles apply: it may subjectively reduce drowsiness while leaving objective impairment in place.

If you’re using carbinoxamine and coffee together:

1. Be cautious with timing. If you take an extended-release dose at bedtime, expect some grogginess the next morning. A small coffee with breakfast may help you feel more functional, but don’t assume you’re back to baseline—especially if you need to drive children to school or commute in heavy traffic.
2. Respect the sedative label. If your doctor prescribed carbinoxamine because non-sedating antihistamines didn’t control your symptoms, they likely weighed that sedation risk carefully. Adding large doses of caffeine just to “bulldoze through” daytime drowsiness may defeat the purpose. It’s better to ask if the dose can be adjusted or timed differently.
3. Watch for anticholinergic burden. Dry mouth, constipation, difficulty urinating, or confusion, particularly in older adults, are red flags. Coffee won’t fix these and may worsen dehydration.

As always, if you notice palpitations, severe dizziness, or mental changes on the carbinoxamine–coffee combo, that’s a cue to contact a healthcare professional rather than self-adjusting doses.

Coffee and Chlorpheniramine

Chlorpheniramine (also known as chlorphenamine in some countries) is one of the most widely used sedating antihistamines, appearing in products such as Chlor-Trimeton®, Piriton®, and many cold-and-flu combinations. (Drugs.com)

Its side-effect profile is classic first-generation:

• Drowsiness and sedation are very common—NHS and Drugs.com sources note that nearly all patients experience some level of daytime sleepiness, especially early in therapy (nhs.uk)
• Other frequent issues include dizziness, blurred vision, dry mouth, and constipation. (RxList)

Given that sedation, many people naturally reach for coffee when they’re on chlorpheniramine. But again, caffeine only masks some of those effects:

• It does not reverse slowed reaction time or reduced concentration; it simply raises arousal a bit.
• If the medication is taken repeatedly (for example, 4 mg every 4–6 hours in a bad allergy flare), residual drowsiness can accumulate.

There’s no widely recognised metabolic interaction between caffeine and chlorpheniramine; the main concern is the functional mix of stimulant plus depressant. If you’re using both:

• Prefer smaller, more frequent coffees earlier in the day rather than large doses of caffeine late at night. You don’t want a 5 pm double espresso preventing you from getting the restorative sleep your immune system needs while chlorpheniramine is still on board.
• Remember that most advice sheets recommend not driving, cycling, or operating machinery while you see how chlorpheniramine affects you. That advice still applies even if you feel perkier after a latte. (nhs.uk)

For many people, switching to a second-generation antihistamine during the day and reserving chlorpheniramine for nighttime doses is a good compromise—coffee can then be enjoyed with far less worry about hidden sedation. That’s a discussion worth having with your clinician if you find yourself relying on coffee just to offset daytime drowsiness from Piriton or Chlor-Trimeton.

Coffee and Clemastine

Clemastine is another first-generation H1 blocker, available in some regions as Tavist® or as part of combination cold preparations. It’s slightly less common than diphenhydramine or chlorpheniramine nowadays, but it’s still used for allergic rhinitis, urticaria, and cold symptoms. (MedlinePlus)

Like its cousins, clemastine carries a clear warning for drowsiness, dry mouth, dizziness, and decreased coordination. MedlinePlus emphasises that people should not drive or perform hazardous tasks until they know how they respond, and that side effects may be more problematic in older adults. (MedlinePlus)

Overdose reports highlight that excess clemastine can produce CNS depression ranging from deep drowsiness to coma, along with classic anticholinergic signs like dilated pupils, flushed skin, and fever (Wikipedia). That underscores how powerfully this drug can influence brain function.

Coffee adds its usual mix:

• Caffeine may partially offset perceived sleepiness, allowing someone who took clemastine for a nighttime allergy attack to feel more awake in the morning.
• However, because clemastine’s anticholinergic and sedative actions persist for hours, you may still be slower to react—even if you feel okay after that first mug.

No formal interaction studies have identified direct pharmacokinetic conflicts between clemastine and caffeine. But the functional issues are similar to those of other first-generation antihistamines:

• In younger, healthy people, a small morning coffee after a nighttime clemastine dose is usually tolerated, as long as they don’t drive or perform high-risk tasks while still groggy.
• In older adults, or in those with glaucomaurinary retention, or cardiac disease, combining a strong anticholinergic sedative with large amounts of caffeine can be uncomfortable and risky.

If you rely on clemastine, practical tips include:

• Use the lowest effective dose, ideally in the evening.
• Stick to moderate caffeine during the day, and avoid using coffee to justify risky activities (“I had a double espresso, so I’m fine to drive now”).
• If daytime allergies are a big problem, ask whether a non-sedating option might be safer for routine use, reserving clemastine for occasional severe flares.

Coffee and Diphenhydramine

Diphenhydramine is perhaps the best-known sedating antihistamine worldwide, sold OTC as Benadryl® for allergies and in many “PM” pain relievers and sleep aids like Nytol®. (DrugBank) It’s a potent H1 blocker with strong anticholinergic and hypnotic properties, which is why a 25–50 mg dose at night can knock many people out. (DrugBank)

Caffeine and diphenhydramine often meet in everyday life: you may take a Benadryl for hives or a nighttime cold remedy, then rely on coffee to function at work the next day. Professional interaction monographs acknowledge that diphenhydramine increases and caffeine decreases sedation, and recommend caution because the net effect is unpredictable. (Medscape)

A few specific issues stand out:

1. Residual next-day impairment. Diphenhydramine’s half-life is around 4–8 hours in adults, longer in older adults or in overdose. That means a bedtime dose can still be active the next morning, especially if you took more than recommended. Coffee may make you feel alert, but your driving and decision-making may still be impaired.
2. Sleep architecture. Chronic use of diphenhydramine as a sleep aid can disturb normal sleep patterns, and caffeine—especially later in the day—adds another layer of disruption. You can end up in a cycle of poor sleep at night, heavy coffee in the morning, then higher doses of diphenhydramine to knock yourself out again. Long term, that’s tough on mood, memory, and health. (NCBI)
3. Anticholinergic burden. Diphenhydramine is one of the strongest anticholinergic drugs; long-term cumulative use is linked to increased dementia risk in observational studies. (NCBI) Coffee won’t offset that and may worsen dehydration and constipation in sensitive people.

On the reassuring side, consumer-level interaction checkers found no specific harmful interaction between Benadryl and caffeine at usual doses, while still advising routine caution. (Drugs.com)

Practical advice if you combine the two:

• Use diphenhydramine sparingly and for the short term, ideally under medical guidance.
• If you take it at night, consider limiting caffeine to earlier in the day and avoiding very large morning doses just to “push through” residual grogginess.
• Never assume that coffee makes it safe to drive after a high or repeated dose of diphenhydramine—especially if alcohol, other sedatives, or sleep debt are also in the picture.

If you find yourself needing Benadryl most nights and depending on strong coffee to function in the morning, that’s a sign to talk with a clinician about safer long-term strategies for allergies or insomnia.

Coffee and Hydroxyzine

Hydroxyzine occupies an interesting niche. It’s a first-generation antihistamine used not only for allergic itching and chronic urticaria, but also for anxiety and tension, pre-operative sedation, and sometimes as an adjunct for insomnia. (Mayo Clinic) Common brand names include Atarax® and Vistaril®. (DrugBank)

Like its cousins, hydroxyzine blocks H1 receptors and has anticholinergic properties, leading to drowsiness, dry mouth, and impaired alertness; both Mayo Clinic and WebMD warn patients not to drive or perform tasks requiring coordination until they know how they respond. (Mayo Clinic)

Because hydroxyzine is explicitly used as an anxiolytic, its interaction with coffee warrants special thought:

• Caffeine can worsen anxiety, restlessness, and palpitations, especially in people already prone to panic or generalized anxiety. (Wikipedia)
• Hydroxyzine, in contrast, is trying to calm that anxious system down by adding sedation and reducing histamine-mediated arousal. (Mayo Clinic)

If you drink a lot of coffee while taking hydroxyzine, you may create an internal tug-of-war—one drug trying to quiet your nervous system, the other revving it up. People often describe this as feeling “wired but tired”: jittery on the surface yet mentally foggy underneath. That’s hardly ideal if you’re taking hydroxyzine to cope with anxiety or to sleep.

There is no strong evidence that coffee alters hydroxyzine’s blood levels significantly, and standard interaction resources don’t list caffeine as a major concern. But clinically:

• If hydroxyzine is prescribed primarily for nighttime anxiety or itching, limiting caffeine to the morning and early afternoon will help the medicine do its job at night and protect your sleep.
• If it’s being used during the day for anxiety, consider whether decaf or lower-caffeine options (half-caf, tea, or one small morning coffee) might align better with your treatment goals.

As with other first-generation antihistamines, older adults and people with glaucoma, urinary retention, or certain heart rhythm problems need extra caution; hydroxyzine itself carries warnings about QT-interval prolongation at high doses or in susceptible individuals.( DrugBank) In those settings, keeping caffeine moderate and discussing your full medication list with a clinician is essential.

Important disclaimer: Everything above is general information, not personalised medical advice. Coffee habits, allergy severity, other medications, and underlying health conditions all shape how safe a particular combination is for you. Always talk with your own doctor or pharmacist before making changes to your medicine schedule or dramatically increasing or cutting back caffeine, especially if you have heart disease, are pregnant, are older than 65, or take several other sedating or anticholinergic drugs.