Makena may cause serious side effects including blood clots, allergic reactions, depression, and yellowing of your skin and the whites of your eyes. Call your healthcare provider right away if you think you have symptoms of a blood clot (leg swelling, redness in your leg, a spot on your leg that is warm to touch, or leg pain that worsens when you bend your foot) or symptoms of an allergic reaction (hives, itching, or swelling of the face). The most common side effects of Makena include injection site reactions (pain, swelling, itching, bruising, or a hard bump), hives, itching, nausea, and diarrhea.
We recommend vaccination of FeLV-negative cats allowed to go outdoors or cats having direct contact with other cats of unknown FeLV status. Vaccination is most likely to be useful in kittens and young adult cats, because acquired resistance to infection develops beyond 16 weeks of age. As of 2006, the AAFP recommends primary vaccination of all kittens for FeLV, but the decision to administer booster vaccines is based on risk assessment. Vaccination is not recommended for FeLV-positive cats and indoor cats with no likelihood of exposure to FeLV.
Vitamin B12 is important for cell reproduction, blood formation, brain development, and bone growth. Individuals suffering from the symptoms of low vitamin B12 (or pernicious anemia), such as depression, exhaustion, anemia, and poor memory, may ask their doctor about vitamin B12 injections.  The physician will draw blood to measure the total blood levels of vitamin B12 in your body, and if they are low then B12 injections may be an option. Vitamin B12 injections contain a man-made form of vitamin B12 called cyanocobalamin. You should also speak to your doctor about allergies or other conditions which may have an adverse reaction to vitamin B12.  Though you can self-administer vitamin B12 injections, the safest way is to have someone give you the injection after being trained by a healthcare professional.