What does the QDS medical abbreviation mean?

Written by Zenya Smith11/08/22

Why are there so many abbreviations in healthcare? 

Originally, medical abbreviations were predominantly used during the writing of prescriptions as a short-hand for dose designation – i.e how and when a medication should be taken. Being able to write key information in a simple way is often a time saver for doctors and GPs who see a huge number of patients throughout the day. Having a clear abbreviation can be helpful for pharmacists too as it can minimise the risk of being unable to read handwriting, a misspelling or typo. 

Today, medical abbreviation usage is more widespread in healthcare. There are some which are recognised and used by people other than healthcare professionals too. For example, you’re more likely to tell someone that you’re going for an MRI scan than a Magnetic Resonance Imaging scan, or a CT scan rather than computerised tomography scan. And, if visiting your local doctors surgery, a nurse may tell you they’re measuring your BMI, rather than your body mass index. However there are still a lot of lesser known ones that you may see on a prescription or during a GP appointment, and wonder what they mean. 

What does QDS stand for in medical terms?

QDS is one of the most common abbreviations used on drug prescriptions. Coming from the latin ‘quater die sumendum’ it simply means ‘to be taken four times daily’. 

Other medical abbreviations that denote how medication should be taken may include –

  • a.c. – take before meals
  • a.m – take in the morning
  • o.d – take once a day
  • b.d.s – take twice a day
  • p.c. – take after food
  • p.m- take in the afternoon or evening
  • p.o. –  take by mouth / oral administration
  • q.1.d. – take every day
  • q.1.h. –  take every hour
  • q.2.h. – take every 2 hours
  • q.4.h. – take every 4 hours
  • q.6.h. – take every 6 hours
  • q.8.h. – take every 8 hours 
  • t.d.s / t.i.d. –  take 3 times a day

Don’t rely on abbreviations – Only take medication as directed on the packaging

Because medical abbreviations are for internal communication between healthcare professionals, they should never be used by patients as directions for taking medication. If you’ve been prescribed any form of medication, only take it as directed by your doctor, or as per the instructions on the packet or dosette box, or as advised in a medical care plan

What is the difference between QID and QDS?

As a general rule, there isn’t any difference – Q.I.D is just another way of saying ‘four times a day’ from the latin ‘quater in die’ 

Why do we take medicines around the clock?

Usually when medication is prescribed to you to be taken at different times throughout the day, it’s to ensure there is a sufficient quantity of the drug in your system for it to work correctly. This is particularly important for strong analgesic, or pain relief medications, as the relief will wear off over time. 

Some medications can irritate the stomach and therefore should be taken with food such as a light meal, or even a simple glass of milk. This will help to line the stomach and reduce the likelihood of things like indigestion or inflammation. These medications are usually prescribed around breakfast or dinner time – making them easier to incorporate into a daily routine. 
There are also some medications that you can take at any time of the day or night, such as over the counter ibuprofen or antihistamines. However, while you’re not limited as to when you take them, it’s still really important to leave the right amount of time between doses to avoid too much getting into your system and potentially causing damage. For example, most shop-bought painkillers can only be taken every 4-6 hours. 


older man taking medication at home to stay well in winter

Lists of abbreviations and their intended meanings 

It’s natural to be curious if you see an unfamiliar word or abbreviation when receiving medical treatment. However, medical professionals sometimes use a single abbreviation to mean a few different things, giving them ambiguous meanings. While we’ve listed some of the most common uses below to help you feel more informed, if you come across an abbreviation you’re unsure of, it’s always best to check with your doctor, nurse or pharmacy. 

Abbreviations for medical procedures and conditions  

These are most commonly used in acute care settings such as hospitals or GP practices. 

Common abbreviations for Medical staff 

  • AMHP – approved mental health professional
  • CMHN – community mental health nurse
  • CPN – community psychiatric nurse
  • Dr – doctor
  • FY1 – FY2 foundation doctor (a doctor in their first or second year of clinical training)
  • HCA – healthcare assistant
  • HCSW – healthcare support worker
  • physio – physiotherapist
  • OT occupational therapist
  • RN – registered nurse
  • RNLD – learning disability nurse
  • SLT – speech and language therapist
  • SpR – specialist registrar 
This article is for informational purposes only and not to be taken as medical advice. For medical advice, always consult your GP.

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