Alcohol intake cause the release of certain substances in the body called cathecolamines which will have a positive effect on the part of the body which causes neurocardiogenic syncope
, the reason you may have noticed you have less crises when you drink. However alcohol, will dehydrate you & slow bowel movements, which may explain the constipation
. The more one is stressed the more one feels the urge to drink. The less one weighs and the less one eats and less water one drinks, the more the alcohol one drinks will have a negative effect on one's body. Alcohol often interacts with medication one takes and may reduce their impact or increase their die effects.
How much alcohol one takes does not only depend on how frequently one drinks but how much one drinks at each sitting. As such as decribed above while some alcohol may help your neurocardiogenic symptoms, drinking even if done rarely and heavily and on an empty stomach or dehydrated body can cause other issues including constipation. Overtime you may get used to having to drink to manage stress and feel better and before you realize you may get dependent on it. It would be good to find other methods of managing your stress levels and improving your neurocardiogenic symptoms.
Talk to you doctor for advice.
Wish you all the best and cheers,