As part of the cross‐national collaborative panic study, a double‐blind comparison of alprazolam, imipramine and placebo was performed in Scandinavian outpatients with panic disorder according to DSM‐III; 41 patients were randomly allocated to each drug. Doses were increased for 3 weeks to an average of about 6 mg alprazolam, 150 mg imipramine and a corresponding number of placebo capsules, which were then given for 5 weeks. No more than supportive psychotherapy was given. Key symptoms were rated weekly. The drugs were tapered for 4 or 8 weeks and the patients were followed up for 6 months. Compliance at 3 weeks was 95% for alprazolam, 83% for imipramine and 88% for placebo; at 8 weeks 95% for alprazolam, 73% for imipramine and 46% for placebo. At 3 weeks plasma determination showed that the proportion taking diazepam outside the protocol was 0% for alprazolam, 19% for imipramine and 31% for placebo; at 8 weeks the corresponding proportions were 3%, 11% and 16%. Intention‐to‐treat analysis showed that freedom from panic attacks was obtained for 68% with alprazolam, 61% with imipramine and 34% with placebo. Alprazolam was more effective than imipramine and placebo on anticipatory anxiety and phobic symptoms. Globally rated by physicians and patients, about 60% had complete remission with alprazolam and imipramine and 30% on placebo. At least partial remission was obtained in about 85% with alprazolam, 70% with imipramine and 40% with placebo. Alprazolam had a more rapid onset of action than imipramine on all symptoms. Side effects were generally mild, with a preponderance of drowsiness for alprazolam and anticholinergic effects for imipramine. Tapering was uneventful without significant discontinuation phenomena. During taper and follow‐up, several patients in remission relapsed, leaving approximately 30% patients in complete remission in all groups. To obtain more stable improvement, either long‐term drug treatment or combinations of drug treatment and psychotherapy should be evaluated.

Enhanced respiratory variability and decreased heart rate variability have repeatedly been observed in patients with panic disorder. Prompted by the notion that angiotensin may be involved in the control of respiration, heart rate variability, and anxiety-like behavior, we investigated the putative association between polymorphisms in three angiotensin-related genes and panic disorder-angiotensinogen (AGT), angiotensin converting enzyme (ACE), and angiotensin II (ANG II) receptor type 1 (ATr1) in 72 patients with panic disorder and 504 controls. Allele and genotype distribution of the ATr1 A1166C allele and the AGT M235T did not differ between patients and controls. With respect to the ACE I/D polymorphism, the I allele was found to be more frequent in male (chi(2) = 8.042, df = 1, P = 0.005), but not female, panic disorder patients than in controls. The results of this investigation provide preliminary evidence for the suggestion that angiotensin-related genes may be associated with panic disorder in men.

Our results suggest that the HCRTR2 polymorphism may be of importance for the pathophysiology of panic disorder. The results should be regarded as preliminary until replicated in an independent sample. This indicates that further research on the possible role of orexin in panic disorder may prove rewarding.

We studied kidney function in 124 short-term and long-term lithium outpatients from a population of 127 patients. Glomerular and distal tubular function were measured and correlated with a number of demographic and treatment variables. There was a significant negative correlation between age and glomerular filtration rate. There were no other significant correlations. Tubular function was below normal in 51% of the patients. Glomerular function was below normal in 3% of the patients. We conclude that lithium treatment in non-toxic dose affects kidney function and that tubular function is more affected than glomerular function. Tubular function probably is better than our figures indicate, glomerular function not as good. Types of lithium preparation do not affect kidney function differently nor does combined treatment with neuroleptics.

PD has a favourable outcome in a substantial proportion of patients. However, the illness is chronic and needs treatment. The short-term treatment given in the drug trial had no influence on the long-term outcome.