Medicine Sick Day Rules

Which illnesses cause dehydration?

Dehydration is the loss of fluid from your body. Vomiting, diarrhoea, and fever (high temperature, sweats, shaking) can make you dehydrated. If you are sick once or have diarrhoea once, then you are unlikely to become dehydrated. Having two or more episodes of vomiting or diarrhoea can lead to dehydration: in these cases, you should consider following this advice.

Medicine sick day guidance

Taking certain medicines when you are dehydrated or very unwell can result in you developing a more serious illness. This is because they can increase the risk of dehydration and lead to potentially serious side effects.

If you are at risk of becoming dehydrated with any of the following:

If you are at risk of becoming dehydrated with any of the following:

• Vomiting or diarrhoea (unless only minor)
• Fevers, sweats or shaking

The medicines below should be temporarily stopped and restarted after 24 to 48 hours of eating and drinking normally.

Do not take extra for missed doses

ACE inhibitors

Names ending in ‘pril’ - examples: lisinopril, perindopril, ramipril. A medicine for high blood pressure and heart conditions. If you are dehydrated, these medicines can stop your kidneys working properly.

ARBs

Names ending in ‘sartan’ - examples: losartan, candesartan, valsartan. A medicine for high blood pressure and heart conditions. If you are dehydrated, these medicines can stop your kidneys working properly.

Diuretics

Sometimes called ‘water pills’ - examples: furosemide, bendroflumethiazide, indapamide, spironolactone. Used for excess fluid and high blood pressure. These medicines can make dehydration more likely.

If you have a diagnosis of Heart Failure please contact your surgery for advice before stopping these during illness as a more specific assessment will need to be undertaken by a clinician.

NSAIDs

Anti-inflammatory pain killers - examples: ibuprofen, naproxen, diclofenac. If you are dehydrated, these medicines can stop your kidneys working properly.

Metformin

A medicine for diabetes. Dehydration can make it more likely that you will develop a serious side effect called lactic acidosis.

SGLT2 inhibitors

Names ending in ‘flozin’ - examples: canagliflozin, dapagliflozin, empagliflozin, ertugliflozin. A medication used in the treatment of diabetes, kidney disease or heart failure. These medicines can make dehydration more likely and if you have diabetes can cause acid to build up if you are unwell.