Hi sshubh:
If the form of meditation your father is using is working for him for cultivating abiding inner silence, then there will be no argument coming from here.
Prescription drugs and/or certain foods can affect the urine, but I am not aware of toxicity being an issue. That is helped a lot by AYP's self-paced approach to all practices. If there are any adverse effects, or any that we may be cautious about in advance, then we scale back on whatever practice we are doing until we are sure things are in balance and the results are favorable.
Here is what it says in
Lesson 319 on amaroli:
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">It is not necessary to be drinking a full glass of urine every morning. In fact, it could be undesirable at certain times, or for certain people. There are several factors that could vary the dose. One is the quantity available. Another is the quality. If we have been eating heavily seasoned, salted, or fatty foods, or taking prescription drugs, the urine may be strong. Amaroli is not prohibited in any of these cases. The quantity may be curtailed or diluted with water as needed.<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Similar advice can be found in the
AYP Diet, Shatkarmas and Amaroli book. Others may have different advice. In the end it is up to you to find what works best in your situation.
Wishing you and your father all the best!
The guru is in you.