Medication Administration Timing

Full update November 2021

The timing of medication administration can be a very important consideration for certain drugs. Most meds should be taken at about the same time(s) each day, but some meds must be given at more specific times. Taking such meds at the wrong time can lead to issues, such as causing the medication to be less effective or more likely to cause unwanted side effects.

It can be tough for some patients to take their medications regularly, let alone take medications at specific times. And med administration when patients are in the hospital can get sidetracked by many factors, such as transferring from floor to floor, procedures, or doses that are dropped or spit out. But med timing is important, and with a little help and attention, the ability to stick to specific schedules whether in the outpatient or inpatient setting can be improved. Pharmacy technicians can use the information in this tutorial to help patients take their medications at the right times.


QTY: 4



Felicity is a 62-year-old female for whom you receive an e-Rx for alendronate 70 mg tablets. You check her medication profile and see that this is a new prescription. You also see that she has a couple of additional meds she takes regularly including lisinopril and simvastatin.

Which meds should be TAKEN WITH FOOD OR MEALS?

Medications should be taken with food or meals usually for one of two reasons: food helps to prevent some side effects of the med, or food in the stomach is required for the best/quickest absorption of the drug into the bloodstream.

Meds that may be taken with food to help prevent side effects (stomach upset, nausea, etc) include: amoxicillin/clavulanate (Augmentin [U.S.], Clavulin [Canada]); corticosteroids such as prednisone; NSAIDs such as ibuprofen or naproxen; and opioids such as codeine or oxycodone. It’s also best for patients who take niacin to take it with food to help avoid stomach upset as well as flushing.

Meds that may be taken with food to improve absorption include: some antibiotics, such as amoxicillin/clavulanate, cefuroxime axetil oral suspension (Ceftin), etc; the antidepressant vilazodone (Viibryd); the antipsychotic ziprasidone (Geodon [U.S.], Zeldox [Canada]); someHIV meds, such as etravirine (Intelence) or ritonavir (Norvir); and the cholesterol med lovastatin.

Interestingly, only higher doses of the blood thinner rivaroxaban (Xarelto) must be taken with food. It comes in 10, 15, and 20 mg tablets, but only the 15 and 20 mg doses must be taken with food. This is because as the dose gets larger, absorption becomes more significantly impacted by food.

Some hepatitis C medications must also be taken with food to maximize absorption such as glecaprevir/pibrentasvir (Mavyret [U.S.], Maviret [Canada]) or sofosbuvir/velpatasvir/voxilaprevir (Vosevi).

Which meds should be TAKEN ON AN EMPTY STOMACH?

Medications that should be taken on an empty stomach are usually those that have reduced absorption through the stomach lining and into the blood when there’s food in the stomach. Generally, if a medication must be given on an empty stomach, it’s best to take it about one hour before or two hours after a meal. But product labeling may specify a different interval.

Meds that may be recommended to take on an empty stomach include some antibiotics such as ampicillin, azithromycin extended-release (Zmax [U.S.]), dicloxacillin (U.S.), rifampin (Rifadin), tetracycline; the antifungal voriconazole (Vfend); the calcium channel blocker nisoldipine (Sular [U.S.]); and some HIV meds such as those containing efavirenz (SustivaAtripla, etc).

Note that some meds are specifically affected by dairy products (e.g., milk, cheese). This is because minerals such as calcium, which are found in dairy products, can bind to the med and reduce its effectiveness. Examples of meds that should not be taken at the same time as dairy products include ciprofloxacin and tetracycline.

Proton pump inhibitors, such as omeprazole (Prilosec OTC [U.S.], Losec [Canada]), esomeprazole (Nexium), or lansoprazole (Prevacid), should usually be taken 30 to 60 minutes before meals (before breakfast if dosed once daily and before breakfast and dinner if dosed twice daily). This is so they can work their best to reduce acid levels in the stomach.


Many patients take most of their meds in the morning such as blood pressure meds, diabetes meds, etc, because it may be more convenient for them. However, there are a variety of reasons other than convenience to take meds first thing in the morning.

Taking diuretics (water pills), such as furosemide or hydrochlorothiazide, in the morning is often a good idea to avoid unwanted trips to the bathroom overnight.

Meds that might cause a patient to be more alert, such as ADHD meds like methylphenidate (Concerta, etc) or amphetamine salts (Adderall XR, etc), should usually be taken early in the day to prevent insomnia (difficulty sleeping).

Levothyroxine (Synthroid, etc) is usually best taken first thing in the morning 30 to 60 minutes before eating and four hours before taking supplements such as calcium or iron. This is because its absorption is reduced when there is food or other medications in the stomach. However, the important thing to remember with levothyroxine is consistency. If a patient has been taking it in the morning with food or at bedtime after dinner and is stable, they should continue to take it that way.

Most osteoporosis meds (bisphosphonates), such as alendronate (Fosamax, etc), risedronate (Actonel), or ibandronate (Boniva [U.S.]), should also be taken first thing in the morning 30 minutes (or 60 minutes for ibandronate) before eating. This is because the absorption of these meds is greatly decreased in the presence of food.

The newer formulation of the old drug bromocriptine (Cycloset [U.S.]), that’s used for diabetes, must be given within two hours after waking in the morning. This is because its effects depend on the patient’s circadian rhythms, or cycles of the body related to the time of day.

As you are reviewing Felicity’s e-Rx for alendronate, you notice the extra details in the notes section which say, “Take 30 mins before first meal of the day.” You plan to include this information in the Rx directions.

Which meds should be TAKEN AT BEDTIME?

As with taking meds first thing in the morning, there are a variety of reasons certain meds should be taken at night. The most obvious are meds that help people sleep such as eszopiclone (Lunesta), temazepam (Restoril), zolpidem (Ambien [U.S.], Sublinox [Canada], etc), and others.

Meds that can cause unwanted drowsiness during the day can be taken at bedtime as well. Examples of these meds include clonazepam (Klonopin [U.S.], Rivotril [Canada]) for anxiety, seizures, etc; clonidine (Catapres, etc) for blood pressure or ADHD; or tricyclic antidepressants like amitriptyline (Elavil) or imipramine (Tofranil). Meds that can cause dizziness might also be best given at bedtime, such as doxazosin (Cardura) or terazosin (Hytrin).

Other meds that may be helpful if taken at bedtime include H2-blockers such as cimetidine (Tagamet) or famotidine (Pepcid, etc). These can work overnight, so that heartburn symptoms don’t interrupt sleep.

Some allergy medications, such as diphenhydramine (Benadryl, etc) or levocetirizine (Xyzal [U.S.]), may be recommended to be taken at bedtime due to the potential for drowsiness.

Rectal or vaginal creams and suppositories, such as clotrimazole, metronidazole, or estrogen (Premarin Vaginal Cream, etc), might be more convenient and less messy for patients when they are used at bedtime.

Which meds should be TAKEN AT SPECIFIC TIMES?

The reasons why some medications must be taken at specific times of day vary. One reason might be to space doses out to give the body a break from the med. Another reason might be to ensure there are continuous levels of the drug in the body. For some conditions, the drug is only needed to work at a specific time of day. Here are some examples.

The progestin-only oral contraceptive pill, norethindrone 0.35 mg (Jencycla, etc), must be taken at the same time every day. If this oral contraceptive is taken more than three hours late, the risk of pregnancy increases, and another form of contraception will be needed for at least two days.

Isosorbide mononitrate immediate-release (U.S.) should be taken in two doses daily, spaced seven hours apart. This gives the body a nitrate-free interval to prevent tolerance to the therapeutic effects of the drug. For the same reason, nitroglycerin ointment and transdermal patches should only be left on for 12 to 14 hours a day.

The extended-release enacarbil salt of gabapentin (Horizant [U.S.]) should be taken at about 5 PM each day so that it’s working when symptoms of restless legs syndrome start at bedtime. And Jornay PM (U.S.; methylphenidate ER) for ADHD is dosed as one capsule in the evening between 6:30 PM and 9:30 PM, and starts working the next morning. Note that this is one exception to the general rule that stimulants for ADHD should be taken early in the day to prevent sleep disruptions.

Patients with Parkinson’s disease can have longer hospital stays when doses of their meds (e.g., levodopa-carbidopa [Sinemet, etc]) are delayed. These patients often require their meds to be given at very specific times to control symptoms, such as every one or two hours.

There are also meds that should be spaced apart from other meds by a certain amount of time. This is because the absorption of one med may be decreased by another med. For example, some antibiotics such as fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin, etc) or tetracyclines (doxycycline, minocycline, tetracycline, etc), should not be taken at the same time as other meds that can bind to them and reduce absorption: magnesium-, aluminum-, or calcium-containing antacids; sucralfate (contains aluminum); or multivitamins or supplements containing iron, calcium, or zinc. Patients will be advised to take these antibiotics anywhere from two to four hours before or two to eight hours after taking the med that can bind to it. As another example, the absorption of iron can also be decreased by magnesium-, aluminum-, or calcium-containing antacids and supplements. Doses of iron and antacids or supplements should be taken as far apart as possible, such as by taking iron at least two hours before or four hours after antacids or supplements.

What can I do to help patients remember when to take their medications?

Always include any specific timing instructions given by the prescriber on the prescription label. In addition, you can use auxiliary labels to reinforce the information for the patient.

Be careful about abbreviations in sigs, such as “pc” (after meals), “ac” (before meals), AM, PM, “qhs” (at bedtime), etc. Some of these can be confusing, so clarify with the pharmacist if necessary. For example, “hs” can mean either half-strength or at bedtime. And “qw,” which is intended to mean every week, can be mistaken for other dosing intervals, such as every day. In addition, abbreviations such as q6pm can be misinterpreted as “every 6 hours” or “every 6 hours after meals” instead of “every day at 6 PM.”

Encourage patients to use tools to help them remember to take their medications. This could include calendar alerts, pillboxes, alarms, or medication reminder devices. There are also several medication adherence apps which can help patients manage and keep track of when to take their meds. We have more tips for helping patients stay adherent to their medications in our toolbox, Medication Adherence Strategies, and our technician tutorial, Med Adherence 101.

You begin typing the directions for Felicity’s alendronate 70 mg prescription from the e-Rx sig, “1TPOQW.” You pause when you see the abbreviation “QW.” You know this abbreviation can sometimes be mixed up with other dosing intervals. But you are fairly certain based on the quantity (4) and how you usually see this drug and dose prescribed, that in this case it means once a week. You confirm with the pharmacist to double check. The final directions you type say, “Take 1 tablet by mouth once a week 30 minutes before the first meal of the day.” When preparing the Rx, you apply a “take on an empty stomach” auxiliary label on the package.

What are some special considerations for timing of med administration in the hospital setting?

Getting meds to hospitalized patients for administration at specific times of the day involves many people. From the pharmacy staff member who prepares a dose, to the pharmacy staff member who delivers it, to the nurse who must administer the med, it can get complicated. Plus, it’s important to remember that nurses might have multiple doses to administer to multiple patients at any given time.

Ensure meds are available for nurses to administer on time. This might involve making sure that med carts or the IV batch are delivered on time, a specific med is delivered to a patient care unit on time, or automated dispensing cabinets are restocked promptly. Having meds available for on-time administration can prevent medication errors and help avoid the hassle of nurses needing to re-time meds or change their schedules due to late doses.

In addition to the reasons that outpatients need to take certain meds at specific times of day, it might be necessary for an inpatient to get a med at an exact time so a blood level of the drug can be measured. Pharmacists check the results of these lab tests to make sure the right dose of a med is being given. It is key for blood levels to be drawn at specific times, such as right before or after a dose is given. If a dose is given too late or too early, the blood level might be relatively meaningless and another level will have to be drawn with the next dose. Examples of drugs that require monitoring of blood levels in inpatients include amikacin, cyclosporine, digoxin, gentamicin, phenytoin, tobramycin, and vancomycin.

A med may also need to be given at a specific time if a patient is having a procedure. This occurs when antibiotics (cefazolin, etc) are given pre-operatively. These must be started within a specific timeframe to be most effective at preventing surgical infections.

Keep in mind that when meds are ordered STAT, getting them to the patient is critical. We go into more detail about this in our tutorial, Inpatient Emergencies 101. Some examples of medications that are often ordered STAT include alteplase for stroke, phenytoin or hypertonic saline for neurologic conditions, furosemide for heart failure symptoms, or Kcentra (U.S.) for serious bleeding. Draw attention to STAT orders with bright-colored bins or stickers as they move through the pharmacy, from prep to delivery, so they don’t get lost in the shuffle. Work quickly, but don’t cut corners since errors can cause delays. Tell pharmacists when STATs are ready to check and notify nurses when they’re delivered. Help your team determine how to improve processes for STAT meds, if needed.

Be aware that sometimes meds aren’t ordered STAT and are still needed right away, so it is important to have an awareness of these situations just in case. One thing that can clue you in that a med is needed right away is if it’s a loading dose. Loading doses can be either IV or oral. They are used to quickly boost blood levels of a med when patients require urgent treatment. Usually, loading doses are larger than normal maintenance doses. An example is for IV vancomycin, where a loading dose may be 25 mg/kg/dose and the maintenance dose may be 15 or 20 mg/kg/dose. Another example is phenytoin, where the loading dose is often 1,000 mg or more, given IV or orally. Loading doses can be given all at one time or divided into a few smaller doses given at shorter than usual intervals. For instance, a 1,000 mcg digoxin loading dose may be split up and given as 500 mcg once, then 250 mcg every 6 hours for two doses. Other meds that may be ordered with loading doses include acetylcysteine (for acetaminophen overdoses), alteplase (usually must be given within three hours of stroke symptom onset), amiodarone, caspofungin, clopidogrel, gentamicin, levetiracetam, rivaroxaban (higher doses are used to start therapy for some conditions), or voriconazole. In fact, your pharmacy might have a list of meds that require loading doses. (If this is the case, it’s usually to help improve safety with these meds, since loading doses can be involved in some potentially serious errors.) Review the list so you can be prepared to ensure patients get these meds as soon as possible when they are ordered.

Meds for patients in procedure areas are also usually needed quickly. These include vasoactive meds (nitroprusside, phenylephrine, etc), blood thinners (bivalirudin, heparin, etc), and anesthetics (bupivacaine, lidocaine, etc). If you’re not sure whether to prioritize an order, check with the pharmacist.

Lastly, there can be timing issues with transitions of care. For example, if you take med histories be sure to document the date and time of the patient’s last dose for each of their meds whenever possible. This can help prevent them from getting doses too close together or too far apart.

Cite this document as follows: Technician Tutorial, Medication Administration Timing. Pharmacist’s Letter/Pharmacy Technician’s Letter. November 2021. [371180]

─Continue to the next section for a “cheat sheet” of drugs that should be given at specific times─

“Cheat Sheet” Examples of Some Common Drugs that Must be Given at Specific Times


Drug or Drug Class


With food or meals

Corticosteroids (prednisone, etc)

To reduce stomach irritation


To improve absorption


To reduce flushing & stomach upset

NSAIDs (ibuprofen, naproxen, etc)

To reduce stomach irritation

Opioids (codeine, oxycodone, etc)

To reduce stomach upset

Rivaroxaban (Xarelto) 15 and 20 mg

To improve absorption

Some antibiotics(amoxicillin/clavulanate, cefuroxime axetil oral suspension)

To improve absorption

Some hepatitis C meds (Mavyret, Maviret, Vosevi)

To improve absorption

Some psychiatric meds (vilazodone [Viibryd], ziprasidone, etc)

To improve absorption

On an empty stomach

HIV meds containing efavirenz (Sustiva, Atripla, etc)

To improve absorption

Proton pump inhibitors (esomeprazole, lansoprazole, etc)
(30 to 60 minutes before meals)

To improve effectiveness

Some anti-infectives (ampicillin, azithromycin ER [Zmax], dicloxacillin, rifampin, tetracycline, voriconazole [Vfend], etc)

To improve absorption

In the morning

Bromocriptine (Cycloset, specifically)

To improve effectiveness

Diuretics (furosemide, hydrochlorothiazide, etc)

To avoid urination at night

Levothyroxine (Synthroid, etc)
(take immediately after rising, on an empty stomach)

To improve absorption

Most osteoporosis meds (alendronate, etc)
(take immediately after rising, on an empty stomach)

To improve absorption

Most stimulants (amphetamine salts, methylphenidate, etc)

To prevent insomnia

At bedtime

Drugs that cause dizziness or drowsiness (amitriptyline, clonidine, clonazepam, doxazosin, terazosin, diphenhydramine,etc)

To prevent dizziness or drowsiness during waking hours

H2-blockers (cimetidine, famotidine, etc)

To improve effectiveness for nighttime heartburn symptoms

Sleep aids (eszopiclone, zolpidem, etc)

So they can work when needed

At specific times

Horizant (gabapentin enacarbil ER)
(take at 5 PM)

To be effective when needed

Jornay PM (methylphenidate ER)
(take between 6:30 PM – 9:30 PM)

To be effective when needed

Norethindrone progestin-only oral contraceptive pill (Jencycla, etc)
(take at exact time each day)

To ensure efficacy

Some antibiotics (fluoroquinolones [ciprofloxacin, levofloxacin, etc]; tetracyclines [doxycycline, minocycline, etc])
(space by specific timeframe from antacids and multivitamins/minerals w/ aluminum, calcium, iron, or zinc)

To prevent reduced absorption

Some nitrates (isosorbide mononitrate immediate-release, nitroglycerin ointment and patches)
(space doses so that a nitrate-free period occurs daily)

To prevent tolerance

[November 2021; 371180]

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