Drugs or substances that have a shorter half-life tend to act very quickly, but their effects wear off rapidly, meaning that they usually need to be taken several times a day to have the same effect.

Half-Life. We now turn to exponential decay. One of the common terms associated with exponential decay, as stated above, is half-life, the length of time it takes an exponentially decaying quantity to decrease to half its original amount.

A medication’s biological half-life refers simply to how long it takes for half of the dose to be metabolized and eliminated from the bloodstream. Or, put another way, the half-life of a drug is the time it takes for it to be reduced by half.

It would mean 4 times in a 24 hour period. It says 24 hour period so you know how much time needs to pass before you take your first dose for the next day. You are unlikely to be awake during the night, so take your doses in the day time. The timing I provided is what I would use myself.

QID: Four times a day. QHS: Before bed. Q4H: Every 4 hours. Q6H: Every 6 hours.

Do I need to take each dose exactly twelve hours apart? None of the asthma medications prescribed by your physician needs to be taken exactly twelve hours apart. Twice-a-day usually means morning and evening, on arising and on going to bed, or even at breakfast and supper.

q12H means every 12 hours. This is not the same as twice-daily (bid or BD). q24H means every 24 hours.

Many mistakes result from dosing directions that simply aren’t clear to patients, she said. For example: “Take two pills twice daily,” to many patients means “take two pills a day,” rather than the intended instruction of taking a daily total of four pills, Schwartzberg explained.

b.i.d. (on prescription): Seen on a prescription, b.i.d. means twice (two times) a day. It is an abbreviation for “bis in die” which in Latin means twice a day.

For example: “Take two pills twice daily,” to many patients means “take two pills a day,” rather than the intended instruction of taking a daily total of four pills, Schwartzberg explained.

“Take every 8 hours” generally means the medicine should be taken 3 times a day.

Since the bacteria are stronger, it may be harder to treat your infection the next time around. So unless your doctor says it’s okay to stop early, be sure to finish your entire course of antibiotics.

All antibiotics have a recommended dosing schedule usually between one and four doses in 24 hours.

Studies show that taking antibiotics such as penicillin or erythromycin two or three times a day instead of the usual four works just fine. If taking medicines more than once or twice a day is hard to remember — as it is for many people — ask your doctor if there’s an alternative drug that you could take less often.

There’s an increased risk of side effects if you take 2 doses closer together than recommended. Accidentally taking 1 extra dose of your antibiotic is unlikely to cause you any serious harm. But it will increase your chances of getting side effects, such as pain in your stomach, diarrhoea, and feeling or being sick.

Types of Antibiotic-Resistant Infections

• Methicillin-Resistant Staphylococcus Aureus. Staphylococcus aureus is a pathogen commonly found on the skin or in the nose of healthy people.
• Streptococcus Pneumoniae. Streptococcus pneumoniae bacteria cause many types of illnesses, including pneumonia, a lung infection.
• Carbapenem-Resistant Enterobacteriaceae.

A spoonful of sugar not only makes medicine easier to swallow, but it also might increase its potency, according to a new study. The results show sugar can make certain antibiotics more effective at wiping out bacterial infections.

The Do’s and Don’ts of Taking Antibiotics

• Don’t: Drink Alcohol.
• Do: Take Your Prescription at the Same Time Every Day.
• Don’t: Take Antibiotics With Dairy or Fruit Juice.
• Do: Protect Yourself from the Sun.
• Don’t: Hesitate to Talk to Your Doctor About Your Concerns.

A glass of water can dilute stomach contents and help get an antibiotic through before your belly can get irritated, Tomaka says. While drinking enough water can help prevent nausea from most medications, other drugs need a full glass for proper absorption, he says.