Dopamine dysregulation syndrome (DDS) is a dysfunction of the reward system observed in some individuals taking dopaminergic medications for an extended length of time. It typically occurs in people with Parkinsons disease (PD) who have taken dopamine agonist medications for an extended period of time. It is characterized by self-control problems such as addiction to medication, gambling, or sexual behavior. Signs and symptoms
The most common symptom is craving for dopaminergic medication. However other behavioral symptoms can appear independently of craving or co-occur with it. Craving is an intense impulse of the subject to obtain medication even in the absence of symptoms that indicate its intake. To fulfill this need the person will self-administer extra doses. When self-administration is not possible, aggressive outbursts or the use of strategies such as symptom simulation or bribery to access additional medication can also appear.Hypomania, manifesting with feelings of euphoria, omnipotence, or grandiosity, are prone to appear in those moments when medication effects are maximum;  dysphoria, characterized by sadness, psychomotor slowing, fatigue or apathy are typical with dopamine replacement therapy (DRT) withdrawal. Different impulse control disorders have been described including gambling, compulsive shopping, eating disorders and hypersexuality. Behavioral disturbances, most commonly aggressive tendencies, are the norm. Psychosis is also common. Causes
Parkinsons disease is a common neurological disorder characterized by a degeneration of dopamine neurons in the substantia nigra and a loss of dopamine in the putamen. It is described as a motor disease, but it also produces cognitive and behavioral symptoms.
Contraindications
Vaccination with live-attenuated or live vaccines is not recommended during treatment and should be administered at least four weeks before starting satralizumab. Side effects
The most common side effects observed were the common cold (nasopharyngitis), headache, upper respiratory tract infection, inflammation of the lining of the stomach, rash, joint pain, extremity pain, fatigue and nausea.The FDA label for satralizumab includes a warning for increased risk of infection, including serious and potentially fatal infections – such as potential reactivation of hepatitis B and tuberculosis. Other warnings and precautions for satralizumab include elevated liver enzymes, decreased neutrophil counts and hypersensitivity reactions. Pharmacology
Mechanism of action
Satralizumab is a humanized IgG2 monoclonal antibody that binds to soluble and membrane-bound human interleukin-6 (IL-6) receptors and thereby prevents IL-6-mediated signal transmission through these receptors.IL-6 is a pleiotropic cytokine that is produced by a large number of cell types and is involved in a variety of inflammatory processes. Patients with NMO and NMOSD have elevated levels of IL-6 in cerebro-spinal fluid and serum during periods of active disease. Some of the pro-inflammatory processes involved in NMOSD are thought to involve IL-6, including the formation of pathological autoantibodies against aquaporin-4 (AQP4), and the permeability of the blood-brain barrier to mediators of inflammation. Efficacy
The effectiveness and safety of satralizumab for the treatment of neuromyelitis optica spectrum disorder (NMOSD) were demonstrated in two 96-week clinical studies.A study of satralizumab as monotherapy for NMOSD included 95 adult participants, 64 of whom had antibodies against AQP4 (i.e. were anti-AQP4 positive).