Mehmood T, Khan RAS, Qarni MA, Khalid U, Iftikhar H. Theophylline versus NSAID in the Treatment of Postdural Puncture  Headache in Obstetric Patients. Pak Armed Forces Med J [Internet]. 2024 Jun. 28 [cited 2024 Dec. 25];74(3):808-11. Available from: https://pafmj.org/PAFMJ/article/view/7837