Endocarditis
ACS
Aortic Dissection
Pseudo aneurysm
Necrotizing fasciitis
Pyomyositis
Subcutaneous abscess
PE
Talcosis (trash lung)
Pulmonary hypertension
Pneumothorax (usually due to injecting in neck vessels)
Osteomyelitis
Diskitis
Epidural Abscess (Spinal)
Vertebral Osteomyelitis
Sternal joint osteomyelitis
DVT
Endocarditis
SAH - especially with sympathomimetics such as methamphetamine and cocaine
Brain abscess
Subdural empyema
Botulism - especially with "skin popping" of black tar heroine
CVA
Fungal endophthalmitis
Amaurosis fugax
Sepsis
Neutropenic Fever
Neutropenia (esp. if using cocaine mixed with levimasole)
Cotton fever
Occurs when cotton is<unk> d to filter<unk> s like heroin and due to the exotoxin from Pantoea agglomerans which colonizes cotton plants
HIV related
Toxoplasmosis
Lymphoma
TB
Occurs when cotton is<unk> d to filter<unk> s like heroin and due to the exotoxin from Pantoea agglomerans which colonizes cotton plants
Toxoplasmosis
Lymphoma
Intravenous drug use
Diabetes medications
Radiation exposure 
Tono-Pen use
Drugs of abuse
Fever in traveler
Hazmat exposure
Gastroesophageal reflux disease