Special features

Drug withdrawal — Patient management

By Paul Davison, MSc, MRPharmS, Andrew Husband MSc, MRPharmS, and Alan Worsley PhD, MRPharmS

This article describes the techniques used to withdraw routine drug therapy safely, focusing on the drugs that commonly cause withdrawal effects. It describes drug withdrawal in surgical patients and the treatment of neonatal abstinence syndrome

This article as a PDF (60K)

Paul Davison and Alan Worsley are senior lecturers in pharmacy practice and Andrew Husband is principal lecturer in pharmacy practice, all at the University of Sunderland

SUMMARY

There are many situations in which routine drug therapy will need to be stopped, as described in the first part of this special feature (p363).

This article describes the management of drug withdrawal and dependence.

Panel 1: Switching between antidepressant drugs

SSRI for SSRI
When replacing one selective serotonin reuptake inhibitor (SSRI) with another, the first should be withdrawn before the second is started. With drugs with a long half-life (eg, fluoxetine), the second drug should not be started until four to seven days after the first drug has been withdrawn.

SSRI to TCA
When an SSRI is to be switched to a tricyclic antidepressant (TCA), cross-tapering is recommended (ie, reducing the dose of the SSRI and increasing the dose of the TCA at the same time).

This does depend on the nature of the drug — for example, more serotonergic TCAs such as clomipramine should not be cross-tapered with SSRIs and fluoxetine should be stopped before starting a TCA. This is due to the fact that fluoxetine has active metabolites and a long half-life.

SSRIs or TCAs to moclobemide
If an SSRI or a TCA is to be switched to moclobemide, the SSRI should be withdrawn with a period of two weeks (except for fluoxetine, in which case the patient should be given a five week “washout” period (no drug) before moclobemide is started.

TCAs should be withdrawn at least one week before stopping moclobemide.

Panel 2: Reassuring patients who stop needing antidepressants

Pharmacists should seek to reassure patients by providing the following information:

• Reassurance that antidepressants are not addictive, and that discontinuation symptoms may occur

• Common symptoms that the patient may experience

• The likely duration over which a dose will be reduced

• An indication of when symptoms are likely to occur, and how long they are likely to continue for