methods of modifying - beta blockers

• What are beta blockers? Give an example.

  BBs act on adrenaline and noradrenaline which reduce arousal of the SNS (sympathtic nervous system)

  
  

  BBs are atenolol, which reduces blood pressure and treats various heart problems.

  
  

  theyre beta adrengeric receptors which can't be stimulated by adrenaline, therefore heart rate/blood pressure do not increase and the heeart pumps at a normal rate and it does not need more oxygen .

  
  

  end result is that the person does not feel anxious.
• What are beta blockers mode of action?


  adrenaline/noradrenaline are hormones produced as part of the fight or flight response, the sympathomeduallry pathway, these hormones are immedialty released to tackle a stressor, circluate the blood stream to create a sympathetic response.

  
  

  the hormones combine with beta-adrenergic recoptors located throughout the cardiovasuclar system, mainly in the heart and blood vessels, explaining why heart rate/blood pressure increases during stress.
• what are the two types of beta blockers?

  1. Non selective beta blockers - e.g. propranolol block adrenaline and noradrenaline in other areas of the body. They block beta 1 and beta 2 (B1 and B2) receptors and will therefore affect the heart, liver, kidney.

  
  

  2. Selective beta blockers - e.g. atenolol affects mostly the heart, meaning that they have less effect on other parts of the body, they block only B1 receptors and will cause reduced cardiac output.
• evaluation - effectiveness

  strength -

  - eveidence for effectiveness of BBs

  - Kelly et al review; BBs reduced everyday anxieties associated with exams.

  - can be effective for those with social anxiety disorder, where speaking in public is a major stressor.

  - BBs can be good with drugs BZs (hayes and schulz), to treat psychological symptoms of stress.
• evaulation - effectiveness (counterpoint)

  - dont do anything to remove causes of stress

  - most stress is chronic, but the reielf given by drugs is short term.

  - when a person stops taking the drugs the symptoms return

  - short term symptom reduction can mask long term problems and prevent an individual from tackling them.

  - drug therapy is not a long term solution for stress related anxiety.
• evaluation - ethics

  side effects -

  - beta blockers tend to be mild and temporary, e.g. dizziness, diarrhoea and nausea, blurred vison, cold feet and hands. However stopping taking these drugs will cause heart palpitations or a rise in blood pressure, as the body has become used to the drugs effects in slowing down the sympathetic response.

  
  

  implications for unfair advantage -

  Beta blockers are banned in the use of sports e.g. international Olympic committee, due to the unfair advantage as it enhances performance because a high level performance in sport is the ability to perform under pressure. However it can be seen as ethical because they stop anxiety interfering with performance unlike steroids.

  
  

  social implications -

  the impact of prescribing drugs off label, limited research into these drugs as theyre off lisence, Hsiang Wen Lin found off label BBs had a 52% average use and Chrisopher Wittich found potential issues with lawsuits against doctors and drug companies should there be any adverse affects and there may be issues of valid consent.