Rectal suppositories of 8-methoxsalen produce fewer gastrointestinal side effects than the oral formulation.
BACKGROUND
Gastrointestinal side effects are associated with the oral ingestion of 8-methoxsalen (8-MOP), including the liquid and crystalline formulations.


OBJECTIVE
The objective of this study was to determine whether the gastrointestinal symptoms associated with 8-MOP could be decreased by altering the route of administration.


METHODS
In an open pilot study, 8-MOP rectal suppositories were given to six patients with psoriasis vulgaris who had significant nausea or abdominal pain with the oral liquid form of the drug.


RESULTS
On a scale of 0 to 5, this group of patients reported a mean score of 4.4 for nausea, 0.3 for vomiting, 2.1 for abdominal pain, and 1.3 for headaches with oral 8-MOP. With the suppository form, the mean scores were 0 for nausea, 0 for vomiting, 0 for abdominal pain, and 0 for headaches. These latter values represent scores for the entire treatment period. Clinical severity scores of psoriasis improved from a mean of 6.5 (maximum possible score = 9) at the start of the trial to a mean of 1 at its conclusion. Plasma 8-MOP levels of more than 100 ng/ml were observed in all patients who received the suppositories; in only one patient were the 8-MOP plasma levels significantly higher with the oral form than with the rectal form.


CONCLUSIONS
Rectal suppositories of 8-MOP were associated with significantly fewer gastrointestinal side effects than the oral form of the drug; this was accomplished without compromising clinical efficacy.
Bolognia
J L
JL
Department of Dermatology, Yale University School of Medicine, New Haven, CT 06510, USA.
Freije
L
L
Amici
L
L
Dellostritto
J
J
Gasparro
F P
FP
D015746:Abdominal Pain / Q000139:chemically induced; D000284:Administration, Oral; D000285:Administration, Rectal; D003460:Crystallization; D006261:Headache / Q000139:chemically induced; D006801:Humans; D007422:Intestines / Q000187:drug effects*; D008730:Methoxsalen / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D009325:Nausea / Q000139:chemically induced; D011701:PUVA Therapy; D010865:Pilot Projects; D011565:Psoriasis / Q000188:drug therapy; D012996:Solutions; D013270:Stomach / Q000187:drug effects*; D013488:Suppositories; D014839:Vomiting / Q000139:chemically induced
D012996:Solutions; D013488:Suppositories; D008730:Methoxsalen