Calcichew D3 Forte 500mg/400IU Chewable Tablets (60). Calcichew-D3 Forte Chewable Tablets are lemon flavoured chewable tablets containing calcium and vitamin D3 which are both important substances in bone formation.. Both are found in the diet and vitamin D is also produced in the skin after exposure to the sun.. Calcichew-D3 Forte is used when your diet or lifestyle does not provide enough calcium or Vitamin D or when body requirements are increased.