Into the setting end of life, we have good experience in their use, both continuous and intermittent (more intermittent), I am talking about our experience as a team.  Not many works available in the topic, but general guidelines recommend it use.

Assuming noisy secretions or rattle are problematic we advocate the use of hyoscine hydrobromide in the syringe driver during the last days of life in Wales ,with Glycopyronium as an alternative.  Often we are trating the relatives for this troublesome symptom not the patient and there rae side effects of drowsiness to consider.

Hi, Faye, perhaps you might be interested to do a reappraisal of the article by Wildiers H et al: Atropine, Hyoscine Butylbromide, or Scopolamine Are Equally Effective for the Treatment of Death Rattle in Terminal Care.

Hi Faye

There is no consistent evidence that shows that one antimuscarinic medication is better than another, nor that any medication has a better effect than placebo (Cochrane review). While they clearly have a physiological effect in volunteers and healthy adults, it might be that the symptom mechanism of death rattle is not well worked out. For example, antimuscarinics are great at drying salivary secretions but not good at drying bronchial or pulmonary secretions which may explain the negative effect in some studies (Bennett papers).  

One study even showed that patients dying with a high anticholinergic load (i.e. getting lots of antimuscarinic medication) had almost 3 times greater chance of getting death rattle. Which suggests that these drugs are not protecting against the symptom! (Sheehan paper) 

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• Thank you for your answers.  I completed a literature review a few years ago and do know all these studies.  Thank you Michael Bennett - I presume you are the author of some of these.
• I have put this question out there hoping there is more research.
• Patients with excessive secretions causing noisy breathing & family distress as they listen to their loved one - is a symptom at end of life that is hard to manage.  I conclude that no one intervention or medication is better than another.  Assessment & judgement of how close the patient is to death dictates whether we administer medication intermittently or continuous.  PLUS we assess the whole situation - if family are distressed yes we certainly do give medication - but often it does not help.  Predisposing factors (lung & cerebral tumours, lung infections & inflammation)  are noted but yes when the secretions are pulmonary they are not successfully dried up.
• When I completed the review I did not have access to the Sheehan review (2011).  It is very interesting how it shows that patients with a high anticholinergic load (I presume this might include cyclizine for nausea.  Inhalers and bronchodilators)  had 2.9 times likelihood of noisy respirations.
• Just found a more recent article by Campbell & Yarandi (2013) which studied death rattle and respiratory distress.  One conclusion they make is that 'antisecretory agents did not produce quiet breathing'.
• I was going to complete a small study of patients.  I had access to data because I was a Liverpool Care Pathway educator and auditor for our region.  But my role has changed and time is limited.  I am still very interested and may be able to complete a small study in my workplace - hospice.  Who knows!

I just published an article as attached below which has a way little relevant to the issue being discussed here.

In my experience, I have rarely received a response by a patient who had had excessive upper airway secretions saying she/he had felt better from our palliative medication. Unlike sputum produced in the state of pneumonia, most if not all patients who suffered from excessive upper airway secretions had been in their final hours; communication on this symptom control had lost between us. And even sometimes I don't know if this excessive secretions is a symptom to require a prescription, I mean for the patient herself/himself. For the family, sometimes, education can bring down their anxiety.