To avoid the possibility of medication overdose, interaction or reaction; or to avoid missing a medication — you must pay attention to how often, how, and which medications you take. 
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The American Heart Association offers several great suggestions to help you safely manage your medications:

• Store medications in a cool, dark dry place. Don’t store them in a bathroom or anywhere else that’s prone to moisture.
• Know which medications, including over-the-counter drugs, that shouldn’t be taken at the same time.
• Always take medications the way your doctor tells you to, and for as long as he or she prescribes.
• Remind yourself to refill your prescriptions before you run out.
• To better track your medications, get them all filled at one pharmacy.
• Build a relationship with a pharmacist, and try to always consult with the same one. Don’t be afraid to ask questions.
• Tell each of your doctors about every medication you take, including any over-the-counter and herbal remedies.
• Don’t suffer through side effects. Speak with your doctor about potential ways to prevent them.
• Don’t split or crush any medication unless your pharmacist says it’s OK; it can affect the way the medication works.