This information explains how to manage AVP deficiency (diabetes insipidus) when you are unwell.

AVP deficiency (diabetes insipidus) can be life-threatening if not managed properly. It can cause sodium levels in the blood to become too high or too low. It is not related to diabetes mellitus.

AVP deficiency is a condition where the kidneys cannot retain water. This happens due to a lack of the anti‑diuretic hormone (a hormone that helps the body hold onto water), which is produced by the pituitary gland.

This leads to:

• passing large amounts of urine
• increased thirst

The condition usually requires medication to manage it effectively.

Without treatment (such as DDAVP), people can become severely dehydrated. In extreme cases, this can be fatal.

Important information

• You should consider wearing an emergency bracelet that tells people that you take Desmopressin (and any other important medications like Hydrocortisone and Levothyroxine), or put an alert on your phone.
• You should let family and friends know about your Desmopressin so that they can speak with hospital staff if you are not able to do so.
• If contacting out of hours services such as NHS 24 or an emergency GP, make sure you tell them you have AVP deficiency (Diabetes Insipidus) and are on Desmopressin (DDAVP).

General advice when unwell

In the vast majority of illnesses you should continue your desmopressin as normal.

Do not increase the dose.

Managing specific situations

Heavy cold, blocked nose or sinusitis

• Take desmopressin as normal.
• If using a nasal spray, switch to tablet or melt format for the duration of the illness to make sure you receive the full dose.
• Maintain fluid intake.

Equivalent doses:

• 1 nasal spray desmopressin = 10 micrograms
• Desmopressin tablets = 100 micrograms
• DDAVP melt = 60 micrograms

Get medical assistance if:

• You are unable to take desmopressin and unable to maintain fluid intake.

Vomiting or diarrhoea (more than once)

• Take desmopressin as normal.
• Maintain fluid intake to cover loss.

Get medical assistance:

• Yes – to make sure your DI is stable.
• You will need urgent medical attention if vomiting or diarrhoea is severe or you are unable to retain desmopressin.

Fever or unusually hot temperature (for example on holiday)

• Take desmopressin as normal.
• Maintain fluid intake.
• You are likely to need extra fluid to cover loss.

Get medical assistance:

• Yes – if your urine output remains low.

Excess intake of desmopressin (above prescribed dosage)

• Miss or delay the next desmopressin dose.
• Limit fluid intake until your urine is restored to normal for you.
• Allow symptom breakthrough (thirst and excess urine) before taking the next dose.

Get medical assistance:

• Yes – if your urine output remains low.

After taking desmopressin with large fluid intake

• Miss or delay the next desmopressin dose.
• Limit fluid intake until your urine is restored to normal for you.
• Allow symptom breakthrough (thirst and excess urine) before taking the next dose.

Get medical assistance:

• Yes – if urine output remains low.

If you have missed or cannot take your desmopressin

• Drink to thirst.

Get medical assistance:

• If you have no access to water.

Symptoms requiring urgent medical attention

Attend A&E urgently if you have:

• Headache
• Irritability
• Increasing tiredness
• Nausea
• Loss of appetite
• Muscle cramps
• Confusion
• Reduced level of consciousness

Call 999 if you have:

• Convulsions or seizures

If you are concerned

If you are concerned about your medical condition, get medical advice.

Important for healthcare staff

You should let the healthcare team looking after you know that you need desmopressin as a life‑preserving replacement therapy for your AVP deficiency (Diabetes Insipidus) (not mellitus).

Make sure hospital staff understand that you must receive your desmopressin. Sometimes doctors and nurses might think that desmopressin is not important because it can be given as a nasal spray.

Ask hospital staff to discuss your case with the endocrine team if needed.