Hello, I can understand your concern for your husband. It would have been helpful if you had mentioned what medicines your husband is taking for Parkinson s disease as more commonly the medicines for this disease like Sinemet, Dopamine agonists, and Anticholinergics etc. can induce hallucinations as a side effect. They have to control Parkinson s disease by changing the chemical balance in brain which is responsible for causing hallucinations. I would advise you to take an appointment with the treating doctor and discuss if altering dose of some medicines responsible for hallucinations is possible or some medicines can be changed. I hope this answer is helpful to you. Thank you for choosing HealthcareMagic. Let me know if I can answer any follow up questions. Best, Dr. Viraj Shah