Abstract
The extent and clinical significance of the pharmacokinetic interaction between fluoxetine and haloperidol was studied in 13 schizophrenic patients with prominent negative symptoms. Patients stabilized on chronic low-dose haloperidol (3-8 mg day-1) received additional fluoxetine (20 mg day-1) for 12 consecutive weeks. Mean plasma concentrations of haloperidol increased significantly from 6.5 ± 2.4 nmol l-1 at baseline to 8.8 ± 3.6 nmol l-1 (P <0.01) at week 12 of fluoxetine treatment, but this effect was not associated with an increase in mean extrapyramidal side effects score on the Simpson and Angus Scale. The improvement in negative symptomatology, as measured by the Scale for Assessment of Negative Symptoms, did not correlate significantly with the increase in plasma haloperidol levels. Though our findings confirm that fluoxetine impairs haloperidol clearance, this interaction is unlikely to have adverse clinical consequences, at least in patients chronically stabilized on a low dosage of haloperidol. As fluoxetine is a potent inhibitor of cytochrome P450 (CYP) 2D6, these results also provide indirect evidence for an involvement of CYP2D6 in the metabolism of haloperidol.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 335-339 |
| Number of pages | 5 |
| Journal | Pharmacological Research |
| Volume | 35 |
| Issue number | 4 |
| State | Published - 1997 |
| Externally published | Yes |
Fingerprint
Keywords
- CYP2D6
- Drug interaction
- Fluoxetine
- Haloperidol
- Negative symptoms
- Schizophrenia
ASJC Scopus subject areas
- Pharmacology
Cite this
Interaction between fluoxetine and haloperidol : Pharmacokinetic and clinical implications. / Avenoso, A.; Spina, E.; Campo, G.; Facciola, G.; Ferlito, Marcella; Zuccaro, P.; Perucca, E.; Caputi, A. P.
In: Pharmacological Research, Vol. 35, No. 4, 1997, p. 335-339.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Interaction between fluoxetine and haloperidol
T2 - Pharmacokinetic and clinical implications
AU - Avenoso, A.
AU - Spina, E.
AU - Campo, G.
AU - Facciola, G.
AU - Ferlito, Marcella
AU - Zuccaro, P.
AU - Perucca, E.
AU - Caputi, A. P.
PY - 1997
Y1 - 1997
N2 - The extent and clinical significance of the pharmacokinetic interaction between fluoxetine and haloperidol was studied in 13 schizophrenic patients with prominent negative symptoms. Patients stabilized on chronic low-dose haloperidol (3-8 mg day-1) received additional fluoxetine (20 mg day-1) for 12 consecutive weeks. Mean plasma concentrations of haloperidol increased significantly from 6.5 ± 2.4 nmol l-1 at baseline to 8.8 ± 3.6 nmol l-1 (P <0.01) at week 12 of fluoxetine treatment, but this effect was not associated with an increase in mean extrapyramidal side effects score on the Simpson and Angus Scale. The improvement in negative symptomatology, as measured by the Scale for Assessment of Negative Symptoms, did not correlate significantly with the increase in plasma haloperidol levels. Though our findings confirm that fluoxetine impairs haloperidol clearance, this interaction is unlikely to have adverse clinical consequences, at least in patients chronically stabilized on a low dosage of haloperidol. As fluoxetine is a potent inhibitor of cytochrome P450 (CYP) 2D6, these results also provide indirect evidence for an involvement of CYP2D6 in the metabolism of haloperidol.
AB - The extent and clinical significance of the pharmacokinetic interaction between fluoxetine and haloperidol was studied in 13 schizophrenic patients with prominent negative symptoms. Patients stabilized on chronic low-dose haloperidol (3-8 mg day-1) received additional fluoxetine (20 mg day-1) for 12 consecutive weeks. Mean plasma concentrations of haloperidol increased significantly from 6.5 ± 2.4 nmol l-1 at baseline to 8.8 ± 3.6 nmol l-1 (P <0.01) at week 12 of fluoxetine treatment, but this effect was not associated with an increase in mean extrapyramidal side effects score on the Simpson and Angus Scale. The improvement in negative symptomatology, as measured by the Scale for Assessment of Negative Symptoms, did not correlate significantly with the increase in plasma haloperidol levels. Though our findings confirm that fluoxetine impairs haloperidol clearance, this interaction is unlikely to have adverse clinical consequences, at least in patients chronically stabilized on a low dosage of haloperidol. As fluoxetine is a potent inhibitor of cytochrome P450 (CYP) 2D6, these results also provide indirect evidence for an involvement of CYP2D6 in the metabolism of haloperidol.
KW - CYP2D6
KW - Drug interaction
KW - Fluoxetine
KW - Haloperidol
KW - Negative symptoms
KW - Schizophrenia
UR - http://www.scopus.com/inward/record.url?scp=0030873010&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030873010&partnerID=8YFLogxK
M3 - Article
VL - 35
SP - 335
EP - 339
JO - Pharmacological Research
JF - Pharmacological Research
SN - 1043-6618
IS - 4
ER -