The manufacturers instructions say to discard the pen after four doses or 30 days after its first use, regardless of any remaining liquid. Hans J
Bock G, Chittilapilly E, Basu R, Toffolo G, Cobelli C, Chandramouli V,
Important considerations before combining these medications include: Absolute contraindications : The combination should be avoided in patients with cardiovascular disease, uncontrolled hypertension, hyperthyroidism, glaucoma, during or within 14 days of MAOI use, personal/family history of MTC or MEN2, pregnancy, breastfeeding, or severe gastrointestinal disease Cardiovascular risk assessment : Phentermine increases heart rate and blood pressure, which requires careful monitoring with baseline and follow-up measurements of vital signs and possibly EKG if cardiac history exists Gastrointestinal tolerability : Tirzepatide commonly causes nausea, vomiting, and diarrhea, which may be compounded by phentermine's effects Medication interactions : Tirzepatide may reduce the effectiveness of oral contraceptives during initiation and dose escalation

Vegans who consume no animal products and vegetarians who consume some animal products (e.g., dairy products, eggs, or both) but not meat have a higher risk of developing vitamin B12 deficiency because natural food sources of vitamin B12 are limited to animal foods