Important Phentermine Precautions and Warnings

Being an amine, this prescription weight loss drug is very similar to an amphetamine. Users have reported side effects that were diagnosed as amphetamine-like effects. Theses warnings are to make you aware of the potential hazards involved with taking prescribed drugs. The risks tend to increase with dosage and it’s very important to being under medical supervision while on Phentermine.


It’s important to note that the co-administration of Phentermine and other drugs is NOT recommended. The safety of the combination of it with any other drugs and selective serotonin re-uptake inhibitors (including but not limited to: fluvoxamine, paroxetine, fluoxetine, sertraline) , has yet to be established and is deemed unsafe.

Phentermine HCL tablets are intended for short term exogenous obesity management only and should never be taken without the supervision of a qualified physician.

Heart Valve Disease

Negative reports from those who have taken the Phentermine and Fenfluramine combination revealed that a majority of users experienced valvular heart disease. This disease mainly affects the tricuspid, mitral, and aortic valves in a surprising amount of otherwise healthy individuals. One must not rule out the fact that taking Phentermine alone could also lead to heart problems. In rare instances, this is the case.

Hypertension (Primary Pulmonary)

Aldo known as PPH, Primary Pulmonary Hypertension is usually reported in very rare cases from Phentermine users. This disease targets the lungs and is often fatal in those who have been administered the Fen-Phen combination drug. Again, there are cases (although rare) where users that have taken Phentermine alone have experienced PPH effects. Some PPH side effects to be aware of:

  • Passing out as a result of dizziness
  • Swollen ankles, feet, or toes
  • Chest pains and trouble breathing
  • Skin discoloration (also known as Cyanosis)

Minor Side Effects That Are More Common

  • Sympathomimetic properties can cause hyperactivity
  • Constipation and diarrhea are very common
  • It can be difficult to sleep during the night
  • Symptoms of dysphoria, euphoria, and unexplained depression can occur
  • Blurry vision and dizziness are not uncommon

Tolerance Development

As mentioned above, increasing dosage beyond the recommended amount can result in life threatening circumstances. It’s very common for users to build a tolerance to Phentermine. Some users have been known to increase their dosage to counteract this tolerance. It is advised that no one ever do this.

If a tolerance does develop or you experience any type of side effect, you should stop taking the medication right away and seek assistance from your doctor.

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