Brief answer....given below
Detailed answer...
If this episode of low blood pressure and dizziness was for the first time,then it could be due to heavy work resulting in dehydration which ultimately leads to low levels of sodium and potassium or lack of food for a prolonged time might have resulted in low blood sugar levels and this ultimately led to low blood pressure.
Treatment in such a case requires adequate replenishment of fluids with electrolytes,fruit juices,coconut water etc.
In case you are repeatedly getting bouts of low blood pressure,then you need to be investigated thoroughly as many conditions like hypothyroidism,anemia,heart problems etc can cause low blood pressure.
For proper health you need to do following...
Sleep well 
Do regular aerobic exercises for 45 minutes a day
Quit smoking if any.
Drink moderate amount of alcohol.
Avoid deep fried and greasy foods,junk foods,colas etc.
Take more of fresh fruits,green vegetables and nuts.
Consume chicken and fish and avoid red meat.
Drink plenty of water.

There is no medicine required for it.

I hope it helps,however you may revert to me for any further query.
Best of luck
Thanks

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