Is there any risk of an interaction between pizotifen and sertraline?/nThe question concerns a 27-y

Fråga: Is there any risk of an interaction between pizotifen and sertraline?

The question concerns a 27-year-old woman treated with sertraline (Zoloft) against depression. Treatment with pizotifen (Sandomigrin) for her migraine is planned. She is also taking metoprolol (Seloken), an oral contraceptive and another drug against her migraine (unknown to the questioner).

Sammanfattning: No documented interactions between pizotifen and sertraline have been found in the litterature. The mechanism of action for pizotifen is not clear. Since pizotifen affects the serotonergic system a pharmacodynamic interaction is not impossible.

Svar: No reported interactions between sertraline and pizotifen were found in databases or pharmacological literature.

Pizotifen is used for migraine prophylaxis but its mechanism of action is not fully understood. It has been proposed that pizotifen acts as a serotonergic antagonist on postsynaptic 5-HT2-receptors. However, pizotifen has shown agonistic effects at low concentration (1,2). According to some studies, pizotifen may have some antidepressive effect (1). No case reports of adverse reactions due to pharmacodynamic interactions with serotonin uptake inhibitors have been found.

Sertraline is metabolised by the cytochrome P-450 enzyme system (CYP), mainly CYP3A4 and CYP2D6. It has inhibiting properties on CYP2D6 (3).

Pizotifen is extensively metabolised (4). The main metabolite is the quaternary N-glucuronide. No studies on CYP-mediated metabolism have been found in the literature.

No interactions between pizotifen and the two other known drugs, metoprolol and oral contraceptives, have been found. Pizotifen does not interact with sumatriptan or zolmitriptan according to interaction studies (5). Drugline no 13444 (year 1996)

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