Doctors is this drug safe for me ?!

before i make my decision to take Ephedrine for weight loss and performance enhancing how would it effect me short term and long term, honestly ? If anyone answers this outside the UK i would just like to reitirate Ephedrine is legal here, many thanks in advance.

I am a 16 year old a male at 189 lb if that is relevant

Ephedrine is a powerful chemical with many may pretty serious side effects. Your doctor or neighborhood pharmacist should be able to any questions you have. On a personal note, you are much too young to take medication for weight loss. I know it is the hard way, but exercise and lifestyle changes are the ones that will last and will not give you heart problems (such as the ones the ephedrine can).
Some of the side effect can be
arrhythmia, pulmonary edema (water in your lungs), renal problems, dizziness, nausea, acne, diffiuculty breathing. I am not saying you will get them, but you may get them.And that may is too much of a risk for a 16 year old healthy man to take on.
Go to GNC, get yourself vitamins and protein shakes and start running in the mornings for 30min if you don't have heart problems. See how much better you will feel, and I will think that I prevented a young man from getting on unnecessary and potentially dangerous drug.

P.S. How tall are you? 189 lbs can be completely normal range weight on one person, but overweight on another.

ephedrine is a sympathomimetic, it stimulates the receptors in your body that respond to adrenaline/ epinephrine.

It is a relatively safe drug but as with all the drugs it has its own share of side effects.
Here's a list. Cardiovascular, Genitourinary and neurological should be your main concern.

Adverse drug reactions (ADRs) are more common with systemic administration (e.g. injection or oral administration) compared to topical administration (e.g. nasal instillations). ADRs associated with ephedrine therapy include:[13]