The question concerns a 42-year-old woman treated with citalopram 20 mg daily because of panic diso

Fråga: The question concerns a 42-year-old woman treated with citalopram 20 mg daily because of panic disorder. After three weeks of citalopram treatment the patient got both visual and auditory hallucinations. The treatment was stopped two days ago, and the patient still has auditory hallucinations. The patient also takes 2-4 tablets of Paraflex comp (dextropropoxyphene 45 mg, chlorzoxazone 125 mg, salicylic acid 500 mg) as needed because of rheumatoid arthritis. Have hallucinations been reported as a side-effect to citalopram treatment? Are there any interactions between Paraflex comp and citalopram?

Sammanfattning: Hallucinations have been reported as a side-effects to citalopram treatment in Sweden, but in no case has the patient been treated with citalopram only. There is a theoretical possibility for an interaction between citalopram and dextropropoxyphene, but no case reports have been found.

Svar: The Medline-search has not revealed any information on hallucinations in connection with citalopram treatment. Four cases of hallucinations have been reported to the Swedish Adverse Drug Reactions Advisory Committee (SADRAC). One of these cases was a 63-year-old man on citalopram treatment who received headaches, nausea and auditory hallucinations after drinking half a bottle of light wine. The three other cases concern women, all three of which were treated with concomitant drugs. One 82-year-old woman complained of hallucinations when the dose of Cipramil was increased from 10 to 20 mg daily. When Cipramil was discontinued the hallucinations disappeared. She was also treated with dextropropoxyphene 100 mg daily and anabolic steroids among other drugs.

We have not found any case reports of interactions between citalopram and Paraflex comp. Theoretically citalopram and dextropropoxyphene may interact by inhibiting the liver enzyme CYP2D6 which is partly responsible for the metabolism of both substances.

Hallucinations have been reported, though rarely, as a side-effect to all of the three substances in Paraflex comp.

In the last issue of Läkartidningen (1), the Medical Product Agency summarizes the experiences of citalopram treatment in Sweden since the registration in 1992. We recommend that this case be reported to SADRAC should no other reason for the symptoms be apparent. 1 Biverkningsnytt - Två års uppföljning av Cipramil. Läkartidningen 1994; 91: 4412-4413