The antihypertensive characteristics of prazosin make it a second-line choice for the treatment of high blood pressure.Prazosin is also useful in treating urinary hesitancy associated with benign prostatic hyperplasia, blocking α1-adrenergic receptors, which control constriction of both the prostate and urethra. Although not a first-line choice for either hypertension or benign prostatic hyperplasia, it is a choice for people who present with both problems concomitantly.During its use for urinary hesitancy in military veterans in the 1990s, Murray A. Raskind and colleagues discovered that prazosin appeared to be effective in reducing nightmares. Subsequent reviews indicate prazosin is effective in improving sleep quality and treating nightmares related to post-traumatic stress disorder (PTSD).Prazosin is used off-label in the treatment of insomnia and can produce sedative effects. It has been said to be the only selective α1-adrenergic receptor antagonist which has been used in the treatment of insomnia to any significant degree. It is used at doses of 1 to 12 mg for this purpose. The combination of prazosin and the beta blocker timolol may produce greater sedative effects than either of them alone.The drug is usually recommended for severe stings from the Indian red scorpion. Adverse effects
Common (4–10% frequency) side effects of prazosin include dizziness, headache, drowsiness, lack of energy, weakness, palpitations, and nausea. Less frequent (1–4%) side effects include vomiting, diarrhea, constipation, edema, orthostatic hypotension, dyspnea, syncope, vertigo, depression, nervousness, and rash. A very rare side effect of prazosin is priapism.
Solitary fibrous tumor (SFT), also known as fibrous tumor of the pleura, is a rare mesenchymal tumor originating in the pleura or at virtually any site in the soft tissue including seminal vesicle. Approximately 78% to 88% of SFTs are benign and 12% to 22% are malignant. The World Health Organization (2020) classified SET as specific type of tumor in the category of malignant fibroblastic and myofibroblastic tumors. Signs and symptoms
About 80% of pleural SFTs originate in the visceral pleura, while 20% arise from parietal pleura. Although they are often very large tumors (up to 40 cm. in diameter), over half are asymptomatic at diagnosis. While some researchers have proposed that a SFT occupying at least 40% of the affected hemithorax be considered a "giant solitary fibrous tumor", no such "giant" variant has yet been recognized within the most widely used pleural tumor classification scheme.Some SFTs are associated with the paraneoplastic Doege–Potter syndrome, which is caused by tumor production of IGF-2. Pathophysiology
Recurrent somatic fusions of the two genes, NGFI-A–binding protein 2 (NAB2) and STAT6, located at chromosomal region 12q13, have been identified in solitary fibrous tumors. Treatment
The treatment of choice for both benign and malignant SFT is complete en bloc surgical resection. Prognosis
Prognosis in benign SFTs is excellent. About 8% will recur after first resection, with the recurrence usually cured after additional surgery.The prognosis in malignant SFTs is much more guarded. Approximately 63% of patients will have a recurrence of their tumor, of which more than half will succumb to disease progression within 2 years.