diff --git a/units/src/locktime/absolute.rs b/units/src/locktime/absolute.rs
index 92283468d..6f87b21bd 100644
--- a/units/src/locktime/absolute.rs
+++ b/units/src/locktime/absolute.rs
@@ -2,8 +2,6 @@
 
 //! Provides [`Height`] and [`Time`] types used by the `rust-bitcoin` `absolute::LockTime` type.
 
-#[cfg(feature = "alloc")]
-use alloc::{boxed::Box, string::String};
 use core::fmt;
 
 use internals::error::InputString;
diff --git a/units/src/parse.rs b/units/src/parse.rs
index a2ee0e4db..52ea0e74b 100644
--- a/units/src/parse.rs
+++ b/units/src/parse.rs
@@ -107,10 +107,9 @@ macro_rules! impl_tryfrom_str_from_int_infallible {
 #[macro_export]
 macro_rules! impl_parse_str_from_int_infallible {
     ($to:ident, $inner:ident, $fn:ident) => {
-        #[cfg(all(feature = "alloc", not(feature = "std")))]
-        $crate::impl_tryfrom_str_from_int_infallible!(&str, $to, $inner, $fn; alloc::string::String, $to, $inner, $fn; alloc::boxed::Box<str>, $to, $inner, $fn);
-        #[cfg(feature = "std")]
-        $crate::impl_tryfrom_str_from_int_infallible!(&str, $to, $inner, $fn; std::string::String, $to, $inner, $fn; std::boxed::Box<str>, $to, $inner, $fn);
+        $crate::impl_tryfrom_str_from_int_infallible!(&str, $to, $inner, $fn);
+        #[cfg(feature = "alloc")]
+        $crate::impl_tryfrom_str_from_int_infallible!(alloc::string::String, $to, $inner, $fn; alloc::boxed::Box<str>, $to, $inner, $fn);
 
         impl core::str::FromStr for $to {
             type Err = $crate::parse::ParseIntError;
@@ -143,7 +142,9 @@ macro_rules! impl_tryfrom_str {
 #[macro_export]
 macro_rules! impl_parse_str {
     ($to:ty, $err:ty, $inner_fn:expr) => {
-        $crate::impl_tryfrom_str!(&str, $to, $err, $inner_fn; String, $to, $err, $inner_fn; Box<str>, $to, $err, $inner_fn);
+        $crate::impl_tryfrom_str!(&str, $to, $err, $inner_fn);
+        #[cfg(feature = "alloc")]
+        $crate::impl_tryfrom_str!(alloc::string::String, $to, $err, $inner_fn; alloc::boxed::Box<str>, $to, $err, $inner_fn);
 
         impl core::str::FromStr for $to {
             type Err = $err;