Many people wonder if phentermine and methamphetamine have anything in common. These medications indeed are rather similar and different at the same time. It’s important to understand that both phentermine and methamphetamine (known as meth) have alike chemical properties with amphetamine. However methamphetamine is much stronger. This drug can cause addiction. On one side it can easily lead to abuse and dependence because of its amphetamine’s stimulant effect. On the other side it can suppress your appetite. Phentermine also lows down your appetite. Its stimulant properties are reflected in raising your heart rhythm and blood pressure. You might know that phentermine shows great weight loss results only during the first few weeks of its usage. After a while its appetite suppressing effect decreases.