I feel it is due to kidney stones.You should try and do the kidney cleanse and see if it feels better. The herbs for the Andreas Moritzkidney cleanse are listed below. Soak two tablespoons in two cups of water overnight,bring to a boil and simmer for about 5-10 mins.drink on an empty stomach in 6-8 sips through the day.
All the best.
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Botanical Names for kidney cleanse Herbs:
# Marjoram (Origanum majorana)
# Cat's Claw (Uncaria tomentosa)
# Comfrey Root (Symphytum officinale)
# Fennel Seed (Foeniculum vulgare)
# Chicory Herb (Chichorium intybus)
# Uva Ursi or Bearberry (Arctostaphylos)
# Hydrangea Root (Hydrangea arborescens)
# Gravel Root (Symphytum officinale)
# Marshmallow Root (Althaea officinalis)
# Golden Rod Herb (Solidago virgaurea)