Clonidine has also had some success in clinical trials for helping to remove or ameliorate the symptoms of hallucinogen persisting perception disorder (HPPD).Injection of α2 receptor agonists into the knee joint space, including clonidine, may reduce the severity of knee pain after arthroscopic knee surgery.Light-activated derivatives of clonidine (adrenoswitches) have been developed for research purposes and shown to control pupillary reflex with light in blind mice by topical application. Clonidine suppression test
The reduction in circulating norepinephrine by clonidine was used in the past as an investigatory test for phaeochromocytoma, which is a catecholamine-synthesizing tumor, usually found in the adrenal medulla. In a clonidine suppression test, plasma catecholamine levels are measured before and 3 hours after a 0.3 mg oral test dose has been given to the patient. A positive test occurs if there is no decrease in plasma levels. Pregnancy and breastfeeding
Clonidine is classed by the FDA as pregnancy category C. It is classified by the TGA of Australia as pregnancy category B3, which means that it has shown some detrimental effects on fetal development in animal studies, although the relevance of this to human beings is unknown. Clonidine appears in high concentration in breast milk and nursing infants have approximately 2/3 of serum clonidine concentrations as the mother. Caution is warranted in women who are pregnant, planning to become pregnant, or are breastfeeding.
Diagnosis
Diagnosis is by biopsy, visualising the fungi under the microscope and culture, which show characteristic fungal filaments and vesicles characteristic of the fungi. Other tests include ELISA, immunodiffusion, and PCR with DNA sequencing (so-called DNA barcoding).X rays and ultrasonography may be carried out to assess the extent of the disease. X rays findings are extremely variable. The disease is most often observed at an advanced stage that exhibits extensive destruction of all bones of the foot. Rarely, a single lesion may be seen in the tibia where the picture is identical with chronic osteomyelitis. Cytology of fine needle aspirate or pus from the lesion, and tissue biopsy may be undertaken sometimes. Some publications have claimed a "dot in a circle sign" as a characteristic MRI feature for this condition (this feature has also been described on ultrasound). Differential diagnosis
The following clinical conditions may be considered before diagnosing a patient with mycetoma:

Tuberculous ulcer
Kaposis sarcoma, a vascular tumour of skin usually seen in AIDS. Leprosy
Syphilis
Malignant neoplasm
Tropical ulcer
Botryomycosis, a skin infection usually caused by the bacteria Staphylococcus aureus. Prevention
No vaccine is available. Simple hygienic precautions like wearing shoes or sandals while working in fields, and washing hands and feet at regular intervals may help prevent the disease. Treatment
Surgery combined with itraconazole may be given for up to year when the grains are black. Posaconazole is another option. Voriconazole can be used for infections caused by Fusarium species.Ketoconazole has been used to treat eumycetoma but has many side effects.