Hi & Welcome to HCM. I appreciate your concern for the accidental overdosage of Tizanidine and Oxycodone. Overdosage of Tizanidine can cause drowsiness, lethargy, confusion and coma. Depressed cardiac function is also observed including most often reduced and slow heart beats and a fall in BP. Breathing difficulity due to respiratory depression is another common feature of Tizanidine overdose. Overdosage of Oxycodone can cause constipation, loss of appetite, vomiting, drowsiness, itching, fall in BP, difficulty in breathing, coma and death. There is no home remedy to counteract the toxic effects of these overdosed drugs. At the most you can self induce vomiting (by touching the soft palate or pharynx or by drinking salted water) to remove the remaining unabsorbed tablets from the stomach or the intestines. You are advised to visit the ER for immediate care and administration of specific antidote like Naloxone for Oxycodone overdosage. Hope this answers your query.