Medication sick day rules
When you are unwell with an illness that can cause you to become dehydrated, taking certain medications can increase your risk of becoming more poorly. For this reason, we recommend that you temporarily stop certain medications.
Dehydration is the loss of fluid from your body. When you are experiencing vomiting, diarrhoea or have a fever, there is the potential for you to become dehydrated.
Medicines that should be withheld whilst you are at risk of dehydration include:
| Medicine |
Uses |
Examples |
Risks when dehydrated |
| ACE inhibitors |
High blood pressure, heart conditions |
Ramipril, lisinopril, enalapril |
These medicines can prevent your kidneys from working properly |
| ARBs |
High blood pressure, heart conditions |
Losartan, candesartan, valsartan, telmisartan |
These medicines can prevent your kidneys from working properly |
| Diuretics (water tablets) |
High blood pressure, excess fluid, heart conditions |
Furosemide, bendroflumethiazide, indapamide |
Increased risks of dehydration |
| Biguanides |
Diabetes |
Metformin |
Increased risk of lactic acidosis, a rare side-effect |
| NSAIDs |
Anti-inflammatory, analgesic |
Ibuprofen, naproxen, diclofenac |
These medicines can prevent your kidneys from working properly |
| Sulfonylureas |
Diabetes |
Gliclazide, tolbutamide |
These medicines can increase your risk of having a 'hypo' |
| SGLT2 inhibitors |
Diabetes, heart condition |
Dapagliflozin, empagliflozin, canagliflozin |
Increased risk of diabetic ketoacidosis, a rare side effect |
| ARNI |
Heart failure |
Entresto |
|
These medicines should be safely restarted when you're well (after 24 to 48 hours of eating and drinking normally). When you do this, take them as normal. Do not take extra for the doses you have missed.
Note, this advice does not apply to minor sickness and diarrhoea (i.e. a single episode). If you are sick, or have diarrhoea once, then you are unlikely to become dehydrated. Two or more episodes of sickness or diarrhoea can lead to dehydration, in these cases you should follow the above advice