Acyclovir is an antiviral medication used to treat herpes infections, including genital herpes, shingles, and chickenpox. According to Drug Patent Watch [1], there are no known long-term effects of stopping acyclovir. However, it is essential to follow the prescribed dosage and finish the entire course of treatment to ensure the infection is fully treated.

Valacyclovir is a prodrug of acyclovir, which means it is converted to acyclovir in the body. Valacyclovir is also used to treat herpes infections, and its side effects are similar to acyclovir. The Mayo Clinic [2] lists several side effects of valacyclovir, including headache, nausea, stomach pain, and dizziness. These side effects are generally mild and go away on their own. However, in rare cases, valacyclovir can cause more severe side effects, such as hallucinations, confusion, and kidney problems.

According to MedlinePlus [3], if you stop taking acyclovir or valacyclovir before completing the full course of treatment, the infection may not be fully treated, and the symptoms may return. It is essential to follow the prescribed dosage and finish the entire course of treatment, even if the symptoms disappear.

In conclusion, there are no known long-term effects of stopping acyclovir, but it is crucial to follow the prescribed dosage and complete the full course of treatment to ensure the infection is fully treated. Valacyclovir has similar side effects to acyclovir, and stopping the medication before completing the full course of treatment may result in the symptoms returning. It is always recommended to consult with a healthcare provider before making any changes to your medication regimen.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/ACYCLOVIR
[2] https://www.mayoclinic.org/drugs-supplements/valacyclovir-oral-route/side-effects/drg-20066635?p=1
[3] https://medlineplus.gov/druginfo/meds/a681045.html